Avi Loeb Medium

The Ingenuity helicopter on Mars. (Image credit: NASA)Helicopters fly by using an engine to spin rotor blades, which create lift and thrust by pushing air away, similarly to a bird flapping its wings or a swimmer moving limbs in water. The spinning blades act as rotating wings, generating low net pressure above and high pressure below to produce lift. A tail rotor or a counter-rotating blade system is essential to cancel torque, preventing the body from spinning in the opposite direction. Forward motion is triggered by tilting the blade plane. An image taken from the Orion capsule on April 3, 2026, showing the thin atmosphere of Earth against the blackness of space. (Image credit: Reid Wiseman, NASA)Helicopter propulsion relies on an ambient medium. The blades gain thrust by pushing the surrounding medium in the opposite direction. The typical speed acquired by air around the blades is of order hundreds of meters per second. Momentum conservation implies that the blades can propel the helicopter body to a speed of this magnitude only if they push an air mass comparable to the body’s mass. Since the mass density of air at sea-level is a few hundred times smaller than the average mass per unit volume of a helicopter, the vehicle must push a volume of air that is at least a hundred times larger than the volume of its body in order to move forward at a speed of a hundred meters per second. An artist’s illustration of NASA’s “Skyfall” helicopter mission to Mars in 2028. (Image credit: AeroVironment)NASA had just announced a plan to launch the first nuclear-powered interplanetary spacecraft before the end 2028 on a mission to Mars called Skyfall. This Space Reactor-1 Freedom will carry three small helicopters to explore a possible human landing site on the Martian surface. The same principle of momentum conservation applies to helicopters flying in the thin atmosphere of Mars. This dilute atmosphere, 95% of which is carbon dioxide (CO2), has a mass density that is 1.6% of the Earth’s atmosphere at sea-level. This implies that a Martian helicopter must process a volume of ambient gas that is about 60 times larger than in Earth’s atmosphere, in order to gain a comparable thrust. If CO2-breathing birds had existed in the Martian atmosphere, they would have needed wings that are roughly 8 times larger than oxygen-breathing counterparts on Earth in order to fly at the same speed. The lift of these hypothetical wings would have benefitted from the lower Martian surface gravity, only 38% of that on Earth. Image of Mars and its thin atmosphere. (Image credit: Emirates Mars Mission).But there are Solar System objects with even thinner atmospheres, as announced today in a paper published here in Nature magazine. The Kuiper belt object 2002 XV93 with a diameter of about 500 kilometers was discovered to possess an extremely thin atmosphere with a density that is ten million times smaller than Earth’s atmosphere at sea-level, based on observations of a stellar occultation from 2024. This delicate atmosphere may have been created by volcanic eruptions or a comet strike. In such a thin atmosphere, a helicopter would struggle to push enough gas in order to move around. An artist’s illustration of the Kuiper belt object 2002 XV93 occulting a background star, an event which provided in 2024 evidence for a very thin atmosphere around the object. (Image credit: Ko Arimatsu/NAOJ)As we consider even more dilute environments, one might wonder: are interstellar helicopters feasible? The average gas density in interstellar space is sextillion (10^{21}) times smaller than in the Earth’s atmosphere. This means that a helicopter would need to cross the entire Milky-Way disk before encountering enough gas mass to push its body to a speed of 100 meters per second. Such a journey would take more than the age of the Universe. Intergalactic helicopters are even more impractical, because the mean density of the intergalactic medium is a million times smaller than the interstellar medium. On average, the Universe contains a single proton per cubic meter. This is bad news for cosmic travelers who enjoy helicopter rides. But it is good news for those who enjoy rocket rides, because interstellar space is so dilute that any rocket will not be slowed down by friction on the surrounding medium. Interstellar rockets can reach Earth without much resistance. In contrast to a helicopter, a rocket ejects its burnt fuel gas from its exhaust and does not rely on the ambient medium for propulsion. Even millimeter-thin membranes, in the form of light-sails or pieces of broken Dyson spheres, can traverse the entire Milky-Way without encountering much resistance, as I calculated here, here and here. *** Are there any extraterrestrial probes in persistent orbits around Earth right now? One would imagine that if there were any extraterrestrial satellites in orbit around Earth, the U.S. intelligence agencies would have noticed them. The U.S. Director of National Intelligence, Tulsi Gabbard, surely knows whether there are any unidentified, non-human made probes around Earth. If they exist, will we hear about them through the declassification directive from President Trump? Time will tell. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

Henry Thoreau’s cabin site. (Image credit: The Walden Woods Project)When I met Sergey Brin and Mark Zukerberg in Silicon Valley a decade ago, their net worth was about $30–40 billion. By now, it is 6 times larger. Over the same decade, the net worth of Elon Musk and Jensen Huang grew by a factor of about 60. With AI advancing rapidly, the latter two are projected to become trillionaires over the next few years. This level of wealth is staggering. What is the best way to use it? Reflecting back on my life, my career goal was to earn just the amount of money necessary to buy me freedom. By freedom, I mean the pleasure of pursuing my creative work while minimizing the time spent on running errands. At times, I accepted leadership positions at Harvard and nationwide as a way of giving back to the community that nurtured me. But as soon as these tasks were completed, I returned to the bliss of creative work. There is nothing better than creative work because it delivers new knowledge every day. Within a week, I am invited to play myself for a cameo in a new movie that is currently in production, called: “Sol Hershowitz’s Guide to Extraterrestrial Life,” alongside the professional actors: Brandon Routh, Sarah Cooper and Mickey Rourke. There is no greater privilege than playing myself, either on a movie set or in life. Science offers the privilege of staying curious about the world, without pretending to be the adult in the room that knows more than is actually known. The problem starts when peer pressure from review committees, or failed academics who became YouTube celebrities by pretending to represent science, push back and ask you to play a role other than yourself. My response to them is simple. Given that all of us will not be around within a century, I ignore haters and focus on what is most important to me: playing myself. The recognition that everything is transient and that all of us will die guides our life goals. An even deeper sense of humility is delivered by a grander cosmic perspective. The age of the observable Universe exceeds the maximum lifespan of a human by a factor of 100 million. There are as many stars in the Milky-Way galaxy and as many galaxies within the observable Universe as the number of humans who ever lived on Earth, of order a hundred billion in both cases. Undoubtedly, this realization delivers the message that we are not the central actors on the cosmic stage. We are not located centerstage and we are probably not at the top of the food chain, cosmologically speaking. Our technological civilization will reach an inevitable natural doomsday as soon as the Sun will die. Most sun-like stars formed billions of years before our Sun. We observe their corpses in the form of billions of white dwarfs within the Milky-Way graveyard. Where are the civilizations that might have blossomed around these dead stars? Any survivors must have escaped their birth planet. Some engaged in interstellar travel. Rather than search for radio communications from young civilizations which are still within the habitable zone of their parent star, we should search for technological signatures of `Noah’s arks’ from old, technologically-advanced civilizations. These are the ones whose lessons we want to learn. Instead, mainstream astronomers are focused on the search for microbes and the SETI community focuses on radio communication signals. Over the past five years, the Galileo Project under my leadership brought the search for extraterrestrial technological objects near Earth into rigorous, transparent mainstream science. The Galileo observatories use triangulation to reliably detect, track, and characterize aerial objects in three dimensions, and employ AI to distinguish outliers from human-made technologies. We also study recovered materials from interstellar meteor candidates, to decide whether they are from outside the Solar System and potentially technological in origin. This work is essential for a scientifically credible evaluation of the nature of Unidentified Anomalous Phenomena (UAP), reported by the Pentagon and the U.S. intelligence agencies. Hopefully, the Galileo Project will strengthen the empirical basis for distinguishing Solar System phenomena from genuinely anomalous events associated with extraterrestrial technological objects near Earth. As of now, the ability of the Galileo Project to pursue its goals depends on the generosity of millionaires and billionaires who support it. I sometimes wonder whether I made a strategic mistake by not focusing at first on creating the wealth that would later support the goals of my scientific research. Research funding is a prerequisite for a major breakthrough in answering the most romantic question in science: “Are we alone?” Here’s hoping that the highest net-worth individuals will choose to invest a small portion of their wealth in the quest for the technological products of our cosmic neighbors. We do not need to rely on the declassification of UAP videos by the White House. We can make pioneering discoveries ourselves by simply looking up. All we need is that someone with an ultra-high net worth will read this essay and resonate with its premise. As a realist, I do not hold my hopes high. I also contemplate `Plan B’ in case AI will deliver a technological doomsday for our civilization in the coming years. This outcome might answer Enrico Fermi’s question: “Where is everybody?” As for myself — rather than move to an underground bunker, I plan to retire into a cabin in the local woods with no internet connectivity. I know of at least one suitable property, the foundations of Henry Thoreau’s cabin near Walden Pond, just 10 miles away from my current home. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: Newsmax)Below is a transcript of a new interview I had today with Rob Astorino on the program Saturday Agenda of Newsmax, available in video form here. Rob’s questions are marked below with the label RA, and my answers with AL, respectively. *** RA: President Trump gave a directive to release UFO files. Does this mean we’re finally going to get some answers? Let’s bring in the expert to talk about it. Professor at Harvard University and director of the Institute for Theory and Computation at Harvard. That’s Doctor Avi Loeb. What information do you think that the president might release? I mean what do you think is actually in those files? AL: Thanks for having me. President Trump is breaking new boundaries here and that would be very exciting. There will probably be several waves of release. The first one will involve video files. We’ve seen some blurry videos in the past. They weren’t very informative. My hope is that we will see something more consequential, interesting, intriguing. If we see objects in the sky that we cannot fully understand and members of the Pentagon intelligence agencies cannot figure out, there are two possibilities: either adversarial nations are using technologies that we are not aware of, or maybe we are dealing with something beyond this earth, or non-human made objects, in which case wecan learn about new technologies. We keep launching rockets — that’s what NASA does — where the fuel is carries more mass than the payload. That’s in order to overcome the pull of the Earth’s gravity. However, if, for example, we would have had a way of producing an object with a negative mass, we could have attached it to the payload. If it has exactly the same mass and it’s negative, then the total mass of this system is zero, and it doesn’t feel any gravity. You can just give it a small push and it will escape from the Earth. So, there are possibilities of extending the technologies we’ve used in the past for maneuvering or traveling that we may not be aware of. It’s a learning experience. At the very minimum, it’s important for national security if all the UFOs are produced by humans. But if we happen to find even one out of a million objects that was not produced by humans and is technological, it would be the biggest discovery of human history. And President Trump will go down in history as the person who allowed the scientific community to learn that. RA: So, you know, it used to be that people were embarrassed to say, I saw something in the sky. I didn’t know what it was. It was UFO. And they would keep it to themselves. Now you got airline pilots, Navy and Air Force pilots shooting this video saying, I don’t know what the heck that was. So, it’s becoming much more mainstream. We have a congressman, Tim Burchett, who said: “When I’ve been briefed by government officials on video pictures, some of the best trained pilots in the world have described having close collisions with some sort of aircraft or apparatus. And so, I think it’s time that they come clean. I don’t know if it’s about little green men or flying saucers, Mr. Morgan, but I do think it’s about disclosure. It’s about transparency.” So that’s the thing. I mean, we equate UFOs with, like he said, the little green men or something like that. And must that be the case? AL: No, no not necessarily. Especially if we’re dealing with objects that travel interstellar distances. It takes a long time and biological pilots make no sense. You would expect technological probes that have artificial intelligence. And you know, Albert Einstein said: “If you want your children to be intelligent, read them fairy tales. And if you want them to be even more intelligent, read them more fairy tales.” We are probably not at the top of the food chain, cosmologically speaking, because there are 100 billion stars in the Milky Way galaxy alone, and we should treat our life as a learning experience as to whether any of our neighbors are visiting us. And if they do, we can learn about new technologies, new science, well beyond what we possess right now, because we benefited only from one century of modern science and technology. And look what we have now: artificial intelligence — another frontier promoted by the Trump administration. But the discovery of visitors could be even more consequential for the future of humanity. RA: I know plenty of people who paid. I don’t know what it was to have a star named after somebody, but that’s a whole other story. Jack Nicholson said: “You can’t handle the truth.” I’m among many that think the government has a lot of information that they’re not telling for a variety of reasons. Is it because they think we can’t handle the truth? AL: I don’t think that’s a good reason, because if you find a tennis ball in the backyard of your home and then you sit at dinner with your family members, you will surely tell them that there might be a resident on your street who threw this tennis ball, because this resident might show up at the front door at some point, or affect their life in other ways. And so, it makes no sense to hide this fact from your family members. We are all in the same boat and the government has other responsibilities, especially national security. The Pentagon and the intelligence agencies have to worry about objects produced by adversarial nations. So, it’s really not their duty to worry about what’s outside the solar system. That’s my day job. And I will be delighted to help the Trump administration figure out what these objects are. It’s unclear whether the most intriguing data will be released in the first wave. There must be some data from satellites and other sources that cannot be released because it was collected by classified sensors, and we don’t want adversarial nations to be aware of our capabilities. But nevertheless, if there is something there, we should all know about it. And I will be the first, you know, to respond to this opportunity. President Trump has me at “hello”, if he wants me to help the government figure things out. RA: All right, really quick, because you are a very smart man. And that’s why we bring you on because we really do value your opinion. Do you believe that there is evidence of a non-human alien life form or something that the government has in its possession? AL: I don’t know, I have to see the evidence before telling you. I was never exposed to that evidence and therefore I have no idea. And if they do have such evidence, that would be remarkable. It would make my life worth living as much as for a whole generation. It will inspire humanity to do better. It will change our priorities. Altogether, I think it will bring us to a better place. It is just like realizing that you have a sibling who is more accomplished than you are. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

The vacuum Casimir force on two plane-parallel plates. (Image credit: Wikimedia)The optimal propulsion of a payload to space is without fuel. Our current space rockets rely on carrying the fuel along with the payload for the ride. Most of the fuel energy is wasted in this way, allowing the terminal speed of the payload to grow only logarithmically with increasing fuel mass. The most elegant way out this conundrum is to create artificially a negative mass. Adding a negative mass of equal magnitude to the payload mass would make the total mass of the system on the launch pad zero. This means that the Earth’s gravity will not be pulling the system down. Ignoring friction with air, an infant could kick the zero-mass system from the ground into space where it will continue along its path at its initial speed without ever being slowed down by the Earth’s gravity. This sounds like a pipe dream. But whether a negative mass can be created is a legitimate physics question. Albert Einstein’s theory of gravity, General Relativity, allows negative masses, as discussed in a seminal 1957 paper published here by the physicist Herman Bondi. By now, we learned that the expansion of the Universe is accelerating, suggesting a form of repulsive gravity sourced by a non-zero the energy density of the vacuum, so-called `dark energy’. Apparently, the cosmic vacuum has a positive energy density and a negative pressure that is nearly equal in magnitude. According to General Relativity, cosmic gravity is sourced by the sum of the energy density plus three times the pressure, yielding a negative gravitational effect for the vacuum proportional to minus twice its energy density. Hence, the resulting gravity of the cosmic vacuum is repulsive rather than attractive. This raises the naïve thought that all we need to do in order to create a negative mass, is to bottle up the cosmic vacuum in a container with thin walls, so that the net gravitating mass of the product will be negative. Unfortunately, there is no way to bottle the vacuum in this way to yield a negative mass. All attempts to conceptualize a way of engineering the production of a negative mass failed. So far, we know of no way for producing a negative mass so as to launch a payload to space without fuel. Harold G. “Sonny” White is a mechanical aerospace engineer at NASA who claims to be working on a new thruster concept by utilizing quantum-mechanical effects, so-called “Casimir cavities”, for potential propellant-less thrusters. According to quantum electrodynamics, the vacuum is described as a sea of virtual particles that constantly pop into and out of existence. White claims that his thruster can “push off” these virtual particles — primarily electrons and positrons — to generate thrust without carrying traditional propellant. The Casimir effect (as reviewed here) is a physical force acting on the macroscopic boundaries of a confined space, which arises from the quantum fluctuations of a field. It is named after the Dutch physicist Hendrik Casimir, who predicted the effect for electromagnetic systems in 1948. After a conversation with Niels Bohr, who suggested that the effect had something to do with the vacuum zero-point energy, Casimir formulated the theory predicting a force between neutral conducting plates. The simplest manifestation of the effect is for electromagnetic fields in the presence of two parallel and perfectly conducting plates. Because the electric field must vanish in a perfect conductor, the vacuum only admits fluctuations which satisfy the boundary conditions of zero electric field on the plates. This limits the number of possible fluctuations, or virtual photons, between the plates relative to the outer space, triggering a lower vacuum pressure between the plates and a resultant attractive force between them. Alternatively, the Casimir effect can be understood as an electromagnetic-polarization interaction between the two plates. The Casimir effect is real. In 1997, a direct experiment by Steven K. Lamoreaux quantitatively measured the Casimir force to be within 5% of the value predicted by theory (as reported here). White’s “Quantum Vacuum Thruster” (as described here and here) claims to be “pushing off” the quantum vacuum consisting of a dynamic sea of virtual particles — principally electrons and positrons — that constantly emerge and disappear. White argues that the quantum thrust is generated similarly to a submarine using a propeller to push water. By using custom-designed Casimir cavities — nanoscale structures with strategically placed pillars and walls — White aims to increase the magnitude of negative vacuum energy density. Nevertheless, the implications of the Casimir for propulsion are dubious. The Casimir force is extremely weak. It is obvious that the rest-mass energy of the conducting plates vastly exceeds the vacuum energy modification in between them. This means that the Casimir energy has a negligible contribution to the total rest-mass energy, making it an extremely weak resource for propulsion. Perhaps if we ever detect vehicles of extraterrestrial visitors, we might find some of them to be propelled by manipulations of spacetime. For that reason, we must stay curious to check if there is any evidence for non-human made vehicles in the UFO videos to be released by the White House, following on President Trump’s recent directive (posted here). As I noted yesterday to Bianca in her morning program Across the Nation on Newsmax (accessible here): “We are probably not at the top of the food chain, cosmologically speaking.” Following that interview, I summarized on Fox 32 Chicago here the latest scientific studies within the Galileo Project in search for extraterrestrial technological artifacts, and finally — close to midnight — I explained here in Jesse Weber Live on NewsNation how much we still do not understand. Indeed, there is a lot that we might learn from more accomplished siblings in our family of technological civilizations. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: Newsmax)On April 29, 2026, an earthquake and 15 aftershocks occurred in southern Nevada near the highly restricted Area 51 military installation. The first quake of magnitude 4.4 struck at a depth of around 4 kilometers which is considered very shallow. The aftershocks, ranging in magnitude from 1.5 to 3.7, struck at a similar depth. This is consistent with geological expectations based on the location of faults and seismicity in that region. To produce such an earthquake artificially requires an explosion energy of 2–3 kilotons of TNT, corresponding to a low-yield tactical nuclear weapon (as calibrated by USGS here). Below is a transcript of a new interview I had at midnight last night on Jesse Weber Live of NewsNation, available in video form here. Jesse’s questions are marked with JW, and my answers with AL, respectively. *** JW: Most of the time, if you want to catch a glimpse of a UFO (Unidentified Flying Object), you better be looking up at the skies, right? But there is now a swarm of earthquakes in the Nevada desert that has some thinking maybe they’re looking in the wrong direction. And I say that because those earthquakes happen near Area 51, which has been linked to UFO conspiracies for decades. And this earthquake swarm has some wondering if the two are somehow related. One earthquake and 15 aftershocks were felt in the area, one of those above a magnitude of 4. And even if it isn’t little green men, this classified facility has been used for advanced weapons and aeronautics testing since the 40s. So, could the next generation of weaponry be possibly taken from UFOs? Is that the source of the quakes? Well, we may be getting some answers sooner rather than later because President Trump said Wednesday that his administration will be releasing the government’s UFO files in the near future. He claimed that the material includes accounts that “you wouldn’t believe.” Now, we’ve heard this from the president before, because in February he tasked Secretary of War Pete Hegseth with starting the process of identifying and releasing the UFO files. And since then, lawmakers have been calling for these materials to be made public, finally. Congresswoman Anna Paulina Luna has even promised a press conference addressing what she calls materials of non-human origin. So could we finally learn the truth about UFOs, maybe the mysterious happenings at Area 51 in the near future? Joining me now to help answer those questions, Frank B. Baird, Jr., Professor of Science at Harvard University, Avi Loeb. Avi, always good to see you. What’s going on with the earthquakes? AL: It could be geological, but why would it coincide with the location of Area 51? If it’s produced by humans, then they’re testing some explosives. That would be a natural expectation because the signal comes from a shallow origin near the surface. So, it may well be that they’re testing some new technologies. Area 51 is a testing bed for new technologies that the military is developing. JW: Well, when you say new technologies, do you mean human technologies or do you mean extraterrestrial technologies? AL: I think it’s very unlikely that they have learned something important out of retrieval of materials from crash sites, because we haven’t seen a breakthrough that cannot be explained by the natural progression of our technologies based on year-by-year developments. I haven’t seen evidence for that in the battlefield. I haven’t seen it anywhere else. So, I would suspect that if they do have any unidentified materials, potentially extraterrestrial, they cannot figure it out. That would be my expectation. And once President Trump declassifies some videos or other information, I’m looking forward to analyzing it, trying to figure out what it means, even if it’s not human-made. The government probably has a hard time inferring what it means. JW: So, I actually wrote this down because I wanted to make sure I get it right. When Representative Anna Paulina Luna says that she’s going to hold a press conference about UFOs, she says, “I don’t call them aliens. I use the term inter-dimensional beings.” What are you expecting from her? AL: Well, she is speculating here about a possible interpretation. She is extremely important in bringing disclosure to the forefront and I very much salute her leadership on that. I actually met with her about a couple of weeks ago in my office at Harvard for 90 minutes. And we see eye to eye in terms of what needs to be done. And once the information is out, as a scientist, I can help her and other officials within government figure things out. The fundamental question is whether an object is not human-made? or is it malfunction of cameras? Are we talking about natural phenomena that we haven’t understood until now? So, we need to examine that data. I’m sure that the people in the Pentagon and the intelligence agencies, have other priorities of national security. They are not scientists. And here I am to serve government in figuring things out. JW: I thought it was interesting earlier on the Today Show, we had the crew of the Artemis II. They were asked if there’s other life out there. They agreed. Two of them said there has to be. Did these answers surprise you? AL: Not at all. It’s very likely because there are 100 billion stars like the sun in the Milky Way galaxy alone, and about 10 percent of them have a planet roughly the size of Earth at a similar separation. So, it is very likely we are not at the top of the food chain. When we go even to other planets within the solar system, like Mars, we might find that Martian life existed in the first couple of billions of years of Martian history. And in fact, we might even find oil if we only dare to drill on Mars, because the point is that early Mars had liquid water on its surface, in the form of rivers, lakes and oceans, and very likely had life as we know it. In fact, maybe life was transferred by rocks from Mars to Earth. So, we are all Martians. Drilling and looking for oil would tell us how early life started. Moreover, the oil can be used for energy purposes in the human base that we might want to establish there. We will need to provide also oxygen for breathing and for burning this oil. But I’m very hopeful that there is oil under the Martian ground, because on Earth we found traces of oil dating back to 3.2 billion years ago. And that’s the time when Mars had oceans, rivers, lakes on its surface. As Earth’s twin, it should have had life just like Earth and therefore oil by now, because deposits of dead algae and bacteria ended up making oil on Earth. JW: Tell me we live in 2026 without telling me we live in 2026. What a conversation. Avi Loeb, thank you so much. Always appreciate it. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

A selfie taken by the NASA rover Perseverance, on July 23, 2024. Is Martian life a selfie of terrestrial life? Discovering ancient oil on Mars could answer this question. (Image credit: NASA)Most geologists believe that oil on Earth originated mostly from the remains of ancient marine microorganisms — primarily plankton, algae, and bacteria — that accumulated on seafloors, were buried under layers of sediment, and transformed under the extreme heat and pressure into oil and gas. Most of the organic raw materials are traced to the Mesozoic era, 66 to 252 million years ago, but some deposits are much older, originating from algae and bacteria in ancient seas. Life started on Earth about 4.2 billion years ago in the form of the Last Universal Common Ancestor (LUCA), which was DNA-dated recently here. However, most rocks of that age have been heated so many times that any fossils they may have contained are gone. In 1998, a team led by geologist Birger Rasmussen of the University of Western Australia discovered microscopic drops of fluid oil preserved within mineral grains in rocks more than 3 billion years old in Australia’s Pilbara region. In 2005, Rasmussen reported here evidence that ancient oil in 3.2-billion-year-old rocks in Western Australia was produced from decayed organic matter. He studied two well-preserved sequences of black shale, which are 2.63 and 3.2 billion years old, and discovered thin, discontinuous streaks of cellular material — kerogen, a waxy precursor to fossil fuels formed from organic matter and commonly found in much younger shales that are known oil producers. Both shales also contained microscopic nodules of bitumen, a tar-like remnant left behind when oil migrates out of the shale. Rasmussen concluded that the abundance and extent of the kerogen in the shales indicates that an ancient ocean was already teeming with enough single-celled life 3.25 billion years ago to support widespread oil generation. The history of Earth is marked by various periods. Precambrian spans the period from Earth’s formation, 4.6 billion years ago, to the Cambrian Period’s start, about 0.5388 billion years ago. Within that timeframe, the Archean Period, lasting from about 4 billion to 2.5 billion years ago, was the critical era when Earth’s crust solidified, oceans formed, and the life appeared. The first, simple unicellular organisms, such as cyanobacteria, thrived during this time, producing the oldest fossils known as stromatolites. In 2021, Rasmussen and colleagues reported here the discovery of ancient oil in 1.88-billion-year-old Gunflint stromatolites and microfossils. The thermally altered oil was found to fill pores and fractures and coat grain surfaces, originating from algae and bacteria in ancient Precambrian seas. The presence of oil-bearing fluid inclusions and pyrobitumen in Archean rocks suggests that a large biomass existed on Earth as early as 3.25 billion years ago. Indeed, abundant microbial activity was preserved in 3.4 billion years old colloform pyrite grains from Archean sedimentary environments , as reported in a paper published this month (April 2026) here. But what happened at the same time on Earth’s twin, Mars? As early as 3.25–3.4 billion years ago, Mars was a wet planet. As discussed here, here and here, surface geological features suggest that liquid water existed in Martian rivers, lakes, oceans and aquifers, more than 3 billion years ago. Indeed, the existence of large volumes of liquid water on the surface of Mars was also supported here by seismic and gravity data down to 20 kilometer depths near NASA’s InSight lander. Mars lost the persistent bodies of liquid water on its surface after most of its atmosphere evaporated, as discussed here. Subsequently, the ancient surface water had been incorporated in Martian minerals, buried as ice, sequestered as liquid in deep aquifers, or lost to space. Life could have started on Mars earlier than on Earth. This is because the heat trapped during planet formation scales as the planet’s volume but escapes through its surface. The surface to volume ratio of Mars is 1.87 times larger than that of Earth, implying that it cooled to temperatures capable of supporting the chemistry of life before Earth. If plankton, algae, and bacteria lived in Martian rivers, lakes, oceans, and aquifers, their dead relics could have been subjected to similar processes that produced ancient oil in the 3.25-billion-year Archean rocks studied by Rasmussen. In case Martian oil exists, it could fuel a future Martian economy. Finding it could be of great value to space entrepreneurs like Elon Musk. Underground petroleum deposits could be searched on Mars through the same techniques adopted on Earth, including localization through seismic or gravity surveys, followed by drilling deep boreholes. NASA’s InSight lander recorded over 1,300 marsquakes, as discussed here. Most importantly, the discovery of ancient Martian oil would be of great value also to science, as this oil would provide a record for how early life may have started on Mars and whether it resembled life on Earth. In case the chemistry of early Martian life was the same as life-as-we-know-it in the ancient Precambrian oceans on Earth, this discovery would suggest that perhaps the two planets have a common ancestry. During the Late Heavy Bombardment period, 4.1 to 3.8 billion years ago, a surge of asteroids and comets cratered the Earth and Mars, potentially exchanging microbial life inside the rocks that were transferred between the two planets. Since Mars cooled first to habitable temperatures, this process of panspermia was more likely to deliver Martian life to Earth before it went the other way around. An early `French kiss’ between Earth and Mars could have resulted in identical early microbes on both. With this perspective, we might all be Martians and Musk’s desire to establish a human base on Mars resembles the desire of some adults to return to their childhood home. The first astronauts in the Solar System may have been tiny microbes, predating human astronauts by billions of years. Finding Martian oil as a trace of the chemistry of life-as-we-know-it holds the potential of unraveling our cosmic roots. Let the search begin. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

An image of the asteroid moonlet Dimorphos, taken by NASA’s DART spacecraft 11 seconds before impact at a distance of 68 kilometers. Dimorphos is about 160 meters in length. (Image credit: NASA/Johns Hopkins APL)The NSF-DOE Rubin Observatory in Chile is expected to discover dozens of new interstellar objects within the next decade. These visitors to our cosmic backyard will be flagged by their speed exceeding the value needed to escape from the pull of the Sun’s gravity. Near the Earth’s orbit around the Sun, the escape speed is 42.1 kilometers per second, just a square-root of 2 larger than the Earth’s orbital speed at the Earth-Sun separation (AU). 3I/ATLAS arrived to our vicinity at about 60 kilometers per second. At that fast speed, which outperforms our fastest rockets, it still takes billions of years to travel throughout the entire disk of the Milky-Way galaxy (as calculated here). Interstellar visitors spent that time traveling and offer us an opportunity to learn about the physical conditions at their origin without us needing to travel for billions of years in order to get there. They already invested that time to get here. If such objects are on random trajectories, it is natural to expect most of them to be icebergs that shed a cometary tail of gas and dust once they are warmed by sunlight. The reason is simple and can be illustrated through the example of our latest visitor, 3I/ATLAS. The parent population of 3I/ATLAS was inferred here to deliver a new detectable object within 5 AU every couple of years, implying that there should be about ten trillion such objects right now within the Solar System out to the edge of the Oort Cloud at 100,000 AU. This edge is roughly half-way to the nearest star, implying that each star system in the Milky-Way galaxy needs to produce during its lifespan about ten trillion objects like 3I/ATLAS if what we detected represents the average interstellar abundance of such objects. Given that 3I/ATLAS carried at least a mass 0.1 billion tons, as derived here, the total ejected mass to interstellar space is at least a sixth of the Earth mass per star, a large reservoir which can only be accommodated by the ejection of icebergs during the formation process of a planetary system. A substantial fraction of the building blocks that combine to make rocky planets could be tossed out of their planetary system through gravitational scattering by massive planets or passing stars. Another ejection mechanism is tidal disruption of planets, as I discussed in my paper with Morgan MacLeod, published here. However, 3I/ATLAS arrived on a trajectory that was aligned to within 4.89 degrees with the orbital (ecliptic) plane of the Earth around the Sun. This alignment is unexpected, given that the ecliptic plane is tilted by 60.3 degrees relative to the plane of the Milky-Way disk of stars. If future interstellar objects will show a preference for an ecliptic orientation, then we would have to entertain the possibility that these trajectories were not drawn randomly but might have been designed technologically. In case of a technological origin, the abundance of visitors near Earth could be much higher than average for the same reason that honey bees cluster around flowers. The simplest way to figure out whether an interstellar visitor is a natural iceberg or an interstellar Trojan Horse with a technological interior, is to crash on its surface — in the same fashion that the DART spacecraft impacted the asteroid moonlet Dimorphos on September 26, 2022. A close-up photograph just before impact would unravel the nature of future interstellar objects, labeled as XI/Rubin with X=4, 5, 6 …. In addition to a camera, the interceptor could carry instruments that would probe the composition of the plume of gas or dust around the interstellar object before impact. Even if the object turns out to be a natural iceberg, the instruments onboard the interceptor could check whether the iceberg carries any biological signatures or the building blocks of life-as-we-know-it in the form of organic molecules. This is an entirely new discovery pathway for astrobiology in our search for life beyond Earth. Obviously, crashing on the hard surface of a spacecraft would be an entirely different experience for a DART-like mission. Launching an interceptor on a crash course with an interstellar object, say 4I/Rubin, requires detection of 4I/Rubin at a distance of 5–10 AU and a fast response time. 3I/ATLAS was discovered at a distance of 3.5 AU from Earth on July 1, 2025 and arrived closest to Earth at a distance of 1.8 AU on December 19, 2025, nearly half a year later. If 4I/Rubin will be detected at a distance of 10 AU and will takes a year to get to within 2 AU, then an Earth-based launch at a reasonable speed of 10 kilometers per second could intercept its path and crash on its surface. This requires planning for a target-of-opportunity space mission with a billion dollars budget. The total cost of the less ambitious DART mission was a third of that. The European Space Agency (ESA) plans a mission called Comet Interceptor, to be launched by 2029. The spacecraft will be placed at the second Earth-Sun Lagrange point L2 and wait for up to three years for a long-period Solar system comet or an interstellar object to fly by at a reachable trajectory and speed. The limitation of this mission is that it can propel itself only at a maneuvering speed of up to 1 kilometer per second, equivalent to traversing 1 AU in about 5 years. Unless we are lucky to have an interstellar visitor that arrives very close to this spacecraft, we will not have sufficient time from detection to intercept its path. NASA could do better, if Jared Isaacman will read this essay. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: Greg Wyatt)Following the success of the Artemis II mission, many kids were inspired to go to the Moon. As responsible adults, we should inform our kids that although a trip to the lunar surface sounds like fun, the experience would be worse than breathing asbestos. The rocky surface of the Moon was shattered into sharp powdery and highly abrasive dust generated by asteroid impacts over the past 4.5 billion years. The lunar dust resembles tiny glass fragments, and poses severe hazards to astronaut health. Any construction project of a sustainable lunar base will inevitably raise dust from the lunar surface. This dust will not settle down quickly because the surface gravity there is about one-sixth of that on Earth. But there are more risks involved in spending a long period of time on the Moon. Owing to the absence of a lunar atmosphere, variations in surface temperature are not moderated and shadowed regions are vastly cooler than regions illuminated by sunlight or by Earth-shine. The coldest temperature ever recorded on the Moon is 24 degrees above absolute zero, measured by NASA’s Lunar Reconnaissance Orbiter in permanently shadowed regions within the Hermite Crater near the lunar north pole (as reported here). Cosmic-rays pose another major health hazard for lunar astronauts, with doses 200 times higher than on Earth, potentially triggering cancer, radiation sickness, and cognitive damage. The Moon’s lack of atmosphere and magnetic field allows energetic particles from the Milky-Way galaxy and the Sun to reach the lunar surface directly. The interaction of cosmic-rays with the lunar soil creates neutrons and gamma-rays which add to the total dose. (Image credit: Greg Wyatt)The Earth’s atmosphere and magnetic field do not only shield the human body from cosmic rays but also from micro-meteorites which burn up before reaching the ground. On the Moon, the direct threat of physical injury comes from high-speed micrometeorites raining from the sky above, as well as the lunar dust created by these steady collisions with the lunar surface. The impact speed of micrometeorites is typically several tens of kilometers per second, carrying up to a thousand times more kinetic energy per unit mass compared to bullets fired by a rifle. The latest detailed study of the statistics of lunar micrometeoroids (reported here) implies that the surface area of a human body would experience a single impact per year by a micrometeoroid which is a tenth of a millimeter in diameter, roughly the thickness of a human hair. Serving as a construction worker on a lunar surface for decades is akin to playing Russian roulette. The conditions on Mars are even more extreme because of its larger distance from the Sun. When Elon Musk said: “I would like to die on Mars, just not on impact,” he should have acknowledged that there are more nuanced ways to die on Earth. Ignoring the human health hazards on the Moon or Mars is madness. Sending AI astronauts instead to these hostile environments would be a mark of genius. (Image credit: Greg Wyatt)What is the fine line separating madness from genius? Aristotle noted, “No great mind has ever existed without a touch of madness”. Piotr Ilych Tchaikovsky confessed: “Undoubtedly, I should have gone mad but not for music.” Creative thinking is facilitated by a brain that exhibits less restraint than average. Friedrich Nietzsche argued that what society calls “madness” is often a visionary mind refusing to conform to “venerated custom”. Nevertheless, we should make wise decisions on whether to send humans to the Moon based on hard facts and not wishful thinking. If the health risks are too high, we should instead use robots with artificial intelligence. The impact of cosmic-rays or micrometeorites on a robot body can be fixed by replacing hardware parts in a lunar machine shop, also operated by robots. Our primary responsibility is to preserve the health of humans who create a better future for all of us here on Earth. This should not preclude us from taking risks in space with the help of our technological avatars. (Image credit: Greg Wyatt)In this essay, I featured four amazing watercolors from a series created by the celebrated artist, Greg Wyatt. These watercolors incorporate inspiring statements by Nicolaus Copernicus, Pyotr Ilych Tchaikovsky, Wolfgang Amadeus Mozart, and Walt Whitman. This is the 13th in a sequence of essays, where Greg and I collaborate on the interface between art and science. The first essay in this series, titled “Music of the Cosmic Spheres,” appeared here; the second essay, titled: “Cosmic Waterfalls in Spacetime Cliffs,” appeared here; the third titled “Missing Elements in the Cosmic Jigsaw Puzzle,” appeared here; the fourth essay, titled: “Why Do We Exist?”, appeared here, and the fifth titled “Inspiration from the Stars”, appeared here, the sixth titled: “We Might Understand How the Cosmos Works Before We Understand How Life Works”, appeared here, the seventh titled: “Will the Human Survive for Billions of Years”, appeared here, the eighth titled: “The Butterfly Effect of Intelligence in the Cosmos”, appeared here, the ninth titled: “Benefits of Extraterrestrial Intelligence over AI”, appeared here, the tenth titled: “Übermenschen on Exoplanets” appeared here, the 11th titled: “If You Had an Infinite Research Budget, How Would You Allocate It?” appeared here, and the 12th titled: “Are Human-Made Objects Orbiting Earth?” appeared here. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: The Sun)Could artificial intelligence (AI), machine learning (ML), large language models (LLM) or natural language processing (NLP) help us figure out the nature of Unidentified Flying Object (UFOs) or Unidentified Anomalous Phenomena (UAP), by analyzing verbal reports from humans? Today, I received an email from a group of researchers who stated: “We’ve been working on a machine learning project that classifies reports from the National UFO Reporting Center by narrative “dramaticness,” essentially modeling the language and content of witness reports to distinguish brief, ambiguous observations from highly detailed extraordinary accounts. The pipeline combines structured features, free-text NLP, gradient-boosted models, and an LLM baseline, with explainability built in. We see this as a content-side complement to instrument-side efforts like the Galileo Project: the witness reports are noisy and selection-biased, but they’re also the longest continuous record of public UAP reporting we have, and the language inside them turns out to carry a lot of structure.” My response clarified the following fundamental points. In scientific research, low significance data is most abundant but is of little use because it is often swamped by noise. UFOs or UAP are a mixed bag with many reports triggered by human-made or natural phenomena. Humans cannot be trusted as scientific detectors. We need instruments to document the evidence. This is evident from the legal system, where convicts who were put on death row based on eyewitness testimonies under oath, were later exonerated based on DNA tests. Among 51 cases of death row exonerations, a study posted here found that 45.9% involved informants, while 25.2% involved erroneous eyewitness identification. The same level of misinformation is also evident in common reports on car accidents, where testimonies are often full of imagined narratives and wishful thinking. Stories told by different people about the same car accident are different and sometimes contradictory. Given that there is only one physical reality, they cannot all be correct. Ambiguities are best resolved not by AI/ML/LLM/NLP systems analyzing verbal testimonies, but rather by multiple video cameras observing the car accident. Since humans know about each other’s story, their narratives are often interwoven and correlated. The fundamental question is whether any of them is right. This is well known to FIFA (Fédération Internationale de Football Association), the soccer worldwide organization. Instead of consulting the goalkeeper or the numerous fans in the audience and using AI/LLM to sort through their narratives, FIFA uses advanced camera-based technologies, including Goal-Line Technology (GLT) and Video Assistant Referee (VAR), to confirm goals, offsides, and fouls. GLT uses 14 high-speed cameras to confirm if the ball crosses the line and sends a signal to the referee within one second, while VAR reviews video footage for overall accuracy. We can spend a lifetime chasing ghosts based on verbal reports or low-quality data. The Galileo Project under my leadership is focused on getting high-quality data from multiple observing directions, allowing us to infer the distance, velocity and acceleration of objects in the sky. Without distance measurements, it is difficult to assess how anomalous a moving object is. Having a lot of uncertain information is not of interest to the Galileo Project, irrespective of how advanced the AI/ML system that analyzes it is. On April 17, 2026, President Trump announced in a speech, accessible here, that the first release of classified UFO files will be coming out very soon. As I discussed in a previous essay, posted here, the question is whether the released videos will be the most intriguing ones. Being flooded by blurry videos with no information about the distance of UFOs from the camera will not resolve ambiguities about whether they deviate from the performance envelope of human-made technologies. When information is limited, intelligence has limited powers. It matters less how advanced the AI/ML/LLM/NLP being used is. What matters the most is the quality of the data. A picture is worth a thousand words. For the same reason, high quality data is worth a thousand LLMs. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

A flare from the Sun. (Image credit: NASA)The most abundant stars are dwarf stars with a tenth of the mass of the Sun. They live for trillions of years (as calculated here), over a hundred times longer than the lifespan of the Sun. If intelligent life was common around low-mass stars, we would find ourselves next to a dwarf star in the future. Why do we exist near the Sun right now, cosmologically speaking? This is a question that I have asked a decade ago in a paper published in the Journal of Cosmology and Astroparticle Physics, accessible here. Since dwarf stars are fainter than the Sun, the habitable zone around them — where liquid water may exist on the surface of an Earth-like planet, is closer to the star than the Earth-Sun separation — defined as an Astronomical Unit and abbreviated as AU. For example, the nearest star to the Sun, Proxima Centauri, has a mass of 0.12 solar masses and a luminosity that is just 0.16% of the solar luminosity. Its habitable zone is between 0.023–0.054 AU (as discussed here), corresponding to an orbital period of 3.6–14 Earth’s days. A rocky planet orbiting within this zone experiences strong tides that tend to lock its spin period to its orbital period, similarly to the Earth’s Moon. This tidal locking minimizes the energy of the system, and means that the planet will have a permanent dayside and a permanent nightside. As it turns out, Proxima Centauri hosts two planets within its habitable zone (as reported here): Proxima b with a mass of about 1.1 Earth masses, an orbital radius of 0.05 AU and an orbital time of 11.2 Earth days, and Proxima d with a mass of about 0.26 Earth masses, an orbital radius of 0.029 AU and an orbital period of 5.1 days. Proxima Centauri exhibits violent flares (as reported here) which can strip the atmospheres of close-in planets like Proxima b or Proxima d. In the absence of an atmosphere, these planets would resemble the current Mars, with no liquid water on their surface. This is because surface water can exist in a liquid phase only in the presence of an external atmospheric pressure. The lack of liquid water would in turn deny Proxima b and Proxima d from the opportunity to develop the chemistry of life-as-we-know-it on their surface. The combination of tidal locking and the lack of an atmosphere to moderate differences in surface temperature, implies a large persistent temperature contrast between the permanent dayside and nightside of these planets. Massive stars are less abundant than solar-mass stars. They are also brighter and shorter-lived than the Sun. They dominated the energy output of early galaxies when the Universe was younger and comparable in age to their lifespan. We should not be surprised to find ourselves in the Solar System at the current cosmic epoch, because the Sun’s lifespan of 12.2 billion years (as calculated here) is similar to the present age of the Universe, 13.8 billion years. In a recent paper with my brilliant postdoc, Devesh Nandal, accessible here, we showed that the intense ultraviolet radiation and strong winds of massive stars preclude habitability for the period of time required for complex life to develop on Earth. In particular, a 9 solar mass star sustains a habitable zone for only 30 million years at an orbital radius of about 100 AU, and this brief sliver of potential habitability disappears for stars more massive than 15 solar masses. In addition, early stars in the infant Universe were marked by a low abundance of heavy elements which are essential for making rocky planets and the carbon-based chemistry of terrestrial life. These universal considerations give a plausible explanation to why we do not exist near a massive star in the past or near a dwarf star in the future, but rather near a middle-aged star like the Sun at the present cosmic epoch. Putting politics aside, life could not have been better — cosmologically speaking. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: iStock/Getty)The White House, Congress and several federal agencies are currently investigating a loosely defined list of recent deaths and disappearances of about ten scientists and staff with potential ties to classified research. Congressmen James Comer — who chairs the House Committee on Oversight and Government Reform, and Eric Burlison — who chairs the Subcommittee on Economic Growth, Energy Policy and Regulatory Affairs, stated officially here that they are investigating the cases as a potential threat to national security. Publicly available information shows the circumstances surrounding these deaths and disappearances vary widely. Related families deny a connection between the tragedies associated with their loved ones and prior classified work. In particular, Susan McCasland Wilkerson, wrote here that she wanted to dispel misinformation, since her husband William McCasland was retired for more than a decade before he disappeared, and therefore “It seems quite unlikely that he was taken to extract very dated secrets from him.” Julia Hicks, stated here that her father, Michael Hicks — a JPL scientist, had been struggling with known medical problems before his death a few years ago, and added: “From what I know of my dad, there’s no train of logic to follow that would implicate him in this potential federal investigation … I don’t understand the connection between my dad’s death and the other missing scientists.” In another case, MIT professor Nuno Louriero was killed by the same person who killed two students at Brown University three days earlier, Claudio Valente, who was a classmate of Louriero at the University of Lisbon in Portugal between 1995–2000 but failed to pursue an academic career after struggling socially and dropping out of a physics PhD program at Brown. Valente’s behavior is likely a case of academic grudge and resentment, as Louriero — with similar initial conditions, had a flourishing academic career. President Trump called the pattern of missing scientists possibly random and stated to reporters: “Hopefully, I don’t know, coincidence, whatever you want to call it. But some of them were very important people, and we’re going to look at it over the next short period.” So far, there is no reason to connect the dots or identify a pattern among the different cases. But humans tend to search for patterns even if they do not exist. There are thousands of nuclear and aerospace scientists in the U.S., and people die or go missing all the time. In dozens of television and radio interviews that I had over the past week, I was asked about the missing scientists. This morning on “Wake Up America” in Newsmax, I clarified that I do not believe the cases are connected but the FBI should check if there are adversarial nations behind any one of them. Nevertheless, I also added that the main problem we currently have is that science is missing from our national priorities. Instead of entertaining budget cuts in federal science agencies like NASA, NHI or NSF, the U.S. government should celebrate the benefits of science to global leadership, national security, economic prosperity and national pride, as evident from the success of recent projects like Artemis II, the Webb telescope or the LIGO gravitational-wave observatory. Cutting funding for science while supporting AI and quantum technologies is equivalent to cutting the roots of a tree while watering its brunches. American superiority in science and technology will not last long this way. The computer chips used in the latest AI systems were designed based on the scientific understanding of quantum mechanics through fundamental curiosity-driven research. In short, the problem the U.S. has is not about “missing scientists” but about “missing science” in our national conversations. True, the current culture of science has its challenges. Whereas, evidence-based science offers the best opportunity for us to learn, the pride and prejudice of dogmatic scientists can block that opportunity. As gatekeepers to new knowledge, scientists have the power to suppress innovation. With great powers comes great responsibility. The efficiency of the scientific engine is measured by the number of breakthrough discoveries made relative to the resources allocated to research. Historical evidence suggests that disruptive science has been declining in recent decades, despite the increases in resources and size of the scientific community. Large communities are dominated by regression to the mean. They foster a dogmatic culture that bets on one possibility as the most likely to succeed. The reduced efficiency of scientific discovery in recent decades begs an alternative approach which will spans alternative strategies to explore the unknown. The more we learn, the better we get at coping with our societal challenges. The technologies which make our quality of life better than that of past generations are based on the scientific knowledge we gather. Paying attention to anomalies, namely facts that do not line up with our expectations, could foster revolutionary discoveries. Rather than obsess with depressing cases of death and disappearance of scientists, our federal agencies should promote an inspiring future for U.S. scientific leadership. The best is yet to come, if we will only let it be. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: Getty/Futurism)One of the surprising anomalies of 3I/ATLAS is its exceedingly high fraction of deuterium, amounting to one deuterium (D) in 100 hydrogen (H) atoms in water (as reported here) and one deuterium in 30 hydrogen atoms in the organic molecule of methane (as reported here). The latter D/H fraction of 3.3% is a thousand times above the average cosmic value elsewhere in the Universe. During the Manhattan Project, Edward Teller raised the speculative possibility that the fireball from an atomic bomb explosion might ignite the atmosphere by triggering a fusion reaction of nitrogen (14N) nuclei (as described here). In response, Hans Bethe calculated that ignition of the Earth’s atmosphere or the oceans was extremely unlikely because of radiative losses. A 1946 report, authored by Emil Konopinski, Cloyd Marvin Jr. and Edward Teller (accessible here), concluded that “whatever the temperature to which a section of the atmosphere may be heated, no self-propagating chain of nuclear reactions is likely to be started.” In 1948 Konopinski and Teller published a paper (accessible here) with the first theoretical prediction for the fusion probability of two deuterium nuclei as bomb fuel. Their calculation motivated the development of the hydrogen bomb in two steps. First, the ignition of a plutonium bomb generates high temperature and density conditions, which in the second step trigger the fusion of deuterium fuel. The fear of triggering a chain reaction remained a concern throughout the entire nuclear weapons test program, especially regarding the possibility that powerful underwater tests of hydrogen bombs might ignite oxygen (16O) atoms in water. Both theoretical and experimental data alleviated these concerns. The nuclear age considerations led to the development of nuclear astrophysics, based on the realization that fusion of light elements powers stars. Deuterium fusion was of particular interest for the thermonuclear weapons community around Edward Teller, but also of great interest for understanding how low-mass stars shine. Fast forward to a month ago: March 20, 2026, when a preprint (accessible here) reported that the interstellar object 3I/ATLAS shows an unexpectedly high deuterium abundance of D/H = (3.31 ± 0.34)% for methane. This discovery immediately raised the following question in my mind: If an atomic bomb were to explode inside 3I/ATLAS, would it trigger a chain reaction of deuterium, generating a spark that ignites 3I/ATLAS into a gargantuan atomic bomb? This is not a completely hypothetical question. Following the 1994 Shoemaker-Levy 9 comet impact on Jupiter, Edward Teller proposed to protect Earth from similar impacts by designing a nuclear explosive device equivalent to a gigaton of TNT, roughly the kinetic energy of a kilometer-diameter asteroid (as discussed here and here). This brings me back to my question: If 3I/ATLAS was heading towards Earth and humanity decided to detonate Teller’s envisioned device at its center in order to decimate it, would the device ignite the deuterium-rich nucleus of 3I/ATLAS? If so, how much energy would be released in the resulting nuclear explosion of 3I/ATLAS? Given that the minimum mass of 3I/ATLAS is 160 million metric tons (as calculated in a paper that I co-authored with Valentin Thoss and Andi Burkert, accessible here), the energy released by fusion of its entire deuterium content would be 10 teratons of TNT. This is about 200,000 times bigger than the largest nuclear explosion ever triggered on Earth — the Soviet Union’s Tsar Bomba, which released about 50 megatons of TNT on October 30, 1961. If Teller’s nuclear device were to ignite a deuterium chain-reaction at the center of 3I/ATLAS, it would serve as a match that lights a fireball with 10,000 more energy! My simple back-of-the-envelope calculation before my morning jog at sunrise, indicates that radiative losses would not have saved us from a fusion chain reaction inside 3I/ATLAS. For an opaque object at solid density like 3I/ATLAS, radiative losses occur at the surface before the object disintegrates. My calculations imply that the explosion triggers by Teller’s device would have disintegrated 3I/ATLAS over a hundredth of a second. In order for the radiative losses to compete with the huge energy released, the surface temperature would have had to rise up to a few million degrees. This, in turn, implies an even higher interior temperature — at which deuterium ignites. This means that exploding Teller’s device deep inside an interstellar object like 3I/ATLAS could ignite a self-sustained D-D chain reaction and a gargantuan nuclear explosion in our cosmic backyard. My preliminary estimate suggests that we should be careful in using Teller’s device for planetary defense. If we ever discover an interstellar object similar to 3I/ATLAS heading towards Earth, we will need to come up with an alternative, less explosive protective measure. Here’s hoping that we will never face that risk. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

The interstellar object 3I/ATLAS appears as the central fuzzy dot in this recent image, taken by the Hubble Space Telescope on April 10, 2026. (Image credit: HST/NASA/T. Scarmato)By now, 3I/ATLAS is at a distance of a billion kilometers or 6.7 times the Earth-Sun separation, well beyond Jupiter. Our interstellar visitor appears as a fading dot, similar to the way it looked when it was first spotted in telescope images nearly a year ago, except that right now it is heading away from us back to interstellar space. Given how well aligned its trajectory was with the orbital plane of Earth around the Sun, we might never witness a visitor like it in our lifetime. Observed brightness (apparent magnitude) of 3I/ATLAS as a function of time. (Image credit: M. Eubanks)The brightness of 3I/ATLAS on its way out is elevated relative to its brightness on the way in because of the excess outgassing and dust shedding that it displayed close to the Sun. So far, its fading light curve does not show any evidence for artificial (self-produced) light. We are still waiting for data from NASA’s Juno spacecraft, taken around March 16, 2026 when 3I/ATLAS came closest to Jupiter. As we say goodbye to 3I/ATLAS on its way out of the detectability horizon of our telescopes, it is time to list all of the anomalies it displayed over the past year, grouped thematically (differently than in my past essays): 1. Isotope ratios: 3I/ATLAS displayed an exceedingly high fraction of deuterium amounting to one deuterium in 100 hydrogen atoms in water (H2O, as reported here) and one deuterium in 30 hydrogen atoms in the organic molecule of methane (CH4, as reported here). The measured abundances is up to a thousand times above the average cosmic abundance, more than an order of magnitude higher than found in water in all known comets or meteorites, and three orders of magnitude higher than found in methane on solar system planets. In addition, the 12C/13C ratios (141–191 for CO2 and 123–172 for CO) was reported to exceed typical values found in the Solar System and nearby interstellar clouds or protoplanetary disks. Potential techno-signature: Deuterium and tritium constitute an efficient fuel for nuclear fusion. If a nuclear bomb was to explode on 3I/ATLAS, it could have triggered a chain reaction by igniting the abundant deuterium in it. 2. Mass Budget Discrepancy: The inferred nucleus diameter and number density of its parent population exceed the mass reservoir of planetary disks around old stars (as inferred here and here) by orders of magnitude. More details are available here. Potential techno-signature: Technological probes might cluster in the habitable zone of stars with an abundance that far exceeds the average value in interstellar space. This might reflect focused interest in resources, in analogy to the clustering of bees around flowers. 3. Fined-Tuned Geometry and Timing of Trajectory: 3.1. The retrograde trajectory of 3I/ATLAS is aligned to within 5 degrees with the orbital plane of the planets around the Sun, with a probability of 0.2% (as discussed here). The Milky-Way disk is misaligned with the ecliptic plane by about 60 degrees. This suggests that the trajectory of 3I/ATLAS may have been planned. 3.2. The arrival time of 3I/ATLAS was fine-tuned to bring it to minimum distances of 29 and 54 million kilometers from Mars and Jupiter, respectively, and be unobservable from Earth at perihelion (as discussed here). 3.3. The perijove distance of 3I/ATLAS during its encounter with Jupiter on March 16, 2026 is 53.6 million kilometers, is very close to Jupiter’s Hill radius, 53.5 million kilometers (as discussed here). Potential techno-signature: The orbital plane and arrival time were selected as part of a probing or seeding (with life or gadgets) mission, targeting the habitable zone of the solar system. 4. Abundant organic molecules: Organic molecules in gas phase, such as CH3OH, H2CO, CH4, and C2H6, were discovered after perihelion (as reported here). To survive cosmic-ray bombardment along an interstellar journey that lasted billions of years, these organic molecules must have been buried under a thick layer of material, at least 10-meters in depth. The volatility of methane (CH4) is between that of carbon dioxide (CO2) and carbon monoxide (CO), yet methane was detected in the gas plume around 3I/ATLAS only after perihelion, while CO2 and CO were detected long before perihelion. This puzzle (discussed here) suggests a strange layered composition of the nucleus or a biological origin. Methane and other organic molecules are known bio-markers. Potential bio-signature: Does 3I/ATLAS carry life on it (as discussed here)? 5. Anti-tail: Analysis of the Hubble Space Telescope image of 3I/ATLAS from July 21, 2025 (as discussed here) suggests that the anti-tail before perihelion must have been in the form of a collimated jet towards the Sun that is about ten times longer than it is wide. This is similar to the collimation observed in post-perihelion images. The anti-tail jet extended out to several hundred thousand kilometers. No known comet exhibited a physical sunward jet of this length that is not a perspective effect. The existence of a prominent anti-tail jet towards the Sun on the way of 3I/ATLAS out of the solar system requires a similar coincidence near the opposite pole of the rotation axis (as discussed here). The fact that a collimated jet appears as the sunward anti-tail both before and after perihelion (while reversing direction at perihelion relative to the direction of motion), has a tiny probability of occurring at random, equal to the square of 0.5% or 0.000025. Possible techno-signature: For a technological object, a beam of particles might be used to block the solar wind from impacting the nucleus surface at a relative speed of order 500 kilometers per second. In addition, the veil of dust around 3I/ATLAS is just of the right column needed to block sunlight from hitting the nucleus surface (as discussed here). 6. Symmetric Jet System: Processing of several dozens of Hubble Space Telescope Images from November 2025 to February 2026 by the Larson-Sekanina filter — which removes the circularly-symmetric glow round the nucleus, reveals a system of three mini-jets which are symmetrically separated by 120 degrees from each other (as discussed here, here and here). Possible techno-signature: The symmetric system of 3+1 jets might be associated with technological thrusters, used for stabilizing the three-dimensional motion of 3I/ATLAS (as discussed here). 7. Rotation-axis alignment: At large distances from the Sun, the initial rotation axis of 3I/ATLAS was aligned to within 8 degrees with the sunward direction when it entered the solar system (as reported here). The probability for that is 0.5%. The observed wobble of the pre-perihelion anti-tail jet in the direction of the Sun (as reported here during July and August 2025) requires the base of the jet to be within 8 degrees from the sun-facing pole, with a probability of 0.5%. The gravitational deflection of 3I/ATLAS by 16 degrees at perihelion (as discussed here), is exactly twice the opening angle of the anti-tail before perihelion. This coincidence allows the wobbling jet around the rotation axis to generate an anti-tail in the direction of the Sun before perihelion and a counter jet on the opposite pole after perihelion, with a jet opening angle of 8 degrees on both poles. Possible techno-signature: The sunward alignment of the rotation axis allows for a steady dayside and a steady nightside throughout the inward or outward legs of the journey, maintaining stable surface temperature and illumination on the surface of a technological object. The launch base of the post-perihelion anti-tail jet resided on the nightside of 3I/ATLAS before perihelion and the base of the pre-perihelion anti-tail jet is now on the nightside of 3I/ATLAS after perihelion. For these bases to be active only when facing the Sun, they must be well insulated on the nightside for a period longer than several months. Heat naturally flows by conduction throughout the body of a natural comet, making this insulation requirement difficult to satisfy in a natural rock. 8. Rare arrival direction: 3I/ATLAS arrived from a direction coincident with the radio “Wow! Signal” to within 9 degrees, with a probability of 0.6% (as discussed here). Potential techno-signature: Did the radio signal originated from a companion of 3I/ATLAS or its senders? 9. Unusual chemical composition: Before perihelion, the gas plume surrounding 3I/ATLAS contained much more nickel than iron, as found in industrially-produced nickel alloys, and a nickel to cyanide ratio that is orders of magnitude larger than for thousands of known comets, including 2I/Borisov (as reported here). After perihelion, iron was detected. Potential techno-signature: Nickel overabundance relative to iron is a characteristic of nickel alloys which are produced industrially for aerospace applications. 10. Extreme Polarization: 3I/ATLAS showed extreme negative polarization, unprecedented for all known comets, including 2I/Borisov (as discussed here and here). Potential techno-signature: This unusual polarization may be related to its unresolved geometry or unusual anti-tail. 11. Extreme brightening: Near perihelion, 3I/ATLAS brightened faster than any known comet and was bluer than the Sun (as discussed here). Potential techno-signature: Does this brightening signals artificial lights or charging a technological device by sunlight? 12. Size and mass: The nucleus of 3I/ATLAS is more massive than 1I/`Oumuamua and 2I/Borisov, while moving faster than both (as discussed here and here). Potential techno-signature: Is 3I/ATLAS a Trojan Horse, namely a natural comet that was hitchhiked by a technological civilization which used its resources to navigate it into the habitable zone of the Solar System? Altogether, these anomalies led me to rank 3I/ATLAS as Level 4 on the Loeb Scale (as discussed here, here, here and here). Given that 3I/ATLAS is on its way out of the Solar System, its anomalies might remain unresolved. If the DOE-NSF Rubin Observatory will detect a new object that resembles 3I/ATLAS and indicates that it may have returned, that by itself would constitute a startling technological signature. This time around, we will have to launch a mission that will intercept its path, take a close-up photograph of its nucleus and crash the interceptor with the camera on it. This will be the best way to show that we all have a crush on returning dating partners. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

Schematic illustration of the progenitor of a supermassive black hole in the form of a supermassive star. After the accretion of gas into the supermassive star ends, the star contracts, ignites hydrogen burning, and re-expands into a late phase of instability. Pulsation-driven mass loss then proceeds through discrete ejection episodes that remove weakly-bound envelope material. Earlier shells expand to large radii, whereas the final pre-collapse ejection remains compact and dense, setting the immediate circumstellar environment which explain Webb telescope data on the observed population of `little red dots’. The ejecta carries a characteristic abundance pattern which is consistent with spectroscopic observations by the Webb telescope. The supermassive star then continues toward collapse through a General Relativistic instability owing to Einstein’s gravity and ultimately ends as a heavy black-hole seed for a quasar. (Image credit: Devesh Nandal et al. 2026)Two new papers today provide evidence for the first generation of stars, made solely from the primordial gas of hydrogen and helium left from the Big Bang. Middle-aged stars like the Sun recycle material that was already processed through nuclear fusion in the interiors of stars. However, the primordial material that made first stars had no heavy elements. As a result, it did not cool efficiently and condensed into massive stars. The first stars with masses exceeding ten solar masses, had a surface temperature of up to 10⁵ degrees and acted as efficient factories of ultraviolet radiation. This was a theoretical prediction that I derived with my students and postdocs at Harvard University thirty years ago. The earliest publications included a paper, accessible here, that I co-authored with my former postdoc Volker Bromm and Rolf Kudritzki in 2001. Our calculations demonstrated that the ultraviolet radiation from the early stars would break hydrogen and helium atoms in their vicinity, and result in the emission of a distinct spectral line from a singly-charged helium ion at a wavelength of 0.1640 micrometers, labeled He II λ1640. The theoretical predictions from my research were summarized in two textbooks that I published a decade later, titled: “How Did the First Stars and Galaxies Form?” and “The First Galaxies in the Universe”. Recent spectroscopic observations by the Webb Telescope detected the emission of a strong He II λ1640 spectral line in the vicinity of an early galaxy, labeled GN-z11, at a cosmological redshift of z=10.6. This galaxy existed 13.4 billion years ago, just 400 million years after the Big-Bang. No heavy elements were identified in its spectrum. The properties of the spectral-line source, labeled Hebe, can be explained by a cluster of first-generation stars. A new paper, posted here, studies an alternative source for the ultraviolet radiation in the form of an accreting supermassive black hole. The authors show that a star cluster with a total mass of 10⁵ solar masses can explain the data more naturally. Such a cluster of first generation of stars constitutes the limit of what is expected in theoretical calculations dating back to my work with Bromm and Kudritzki. My interest in this topic started as early as in 1994, shortly after my arrival as junior faculty at Harvard, when I published a paper — accessible here — with Fred Rasio, suggesting that the progenitors of the first supermassive black holes at the centers of galaxies are supermassive stars. Our model suggested that as a result of inefficient cooling, a clump of primordial gas would generically condense at the center of the first galaxies without fragmenting into low-mass stars. The collapse of this primordial cloud would result in a supermassive star that lives for about a million years and eventually collapses to a seed of a quasar black hole. The early population of quasars are known to be black holes which accrete gas at the center of galaxies. Bright quasars peaked in abundance during the first few billion years after the Big-Bang. Other observations by the Webb telescope reveal the existence of a population of `little red dots’, compact reddish galactic cores which existed during the era of quasar formation. Could these `little red dots’ be the seeds of quasar black holes? This was indeed the suggestion we made in a paper that I recently published in collaboration with Fabio Pacucci, accessible here. But there is another new paper that I co-authored today, available here, which was led by my postdoc Devesh Nandal. The paper explains that the spectral properties of `little red dots’ requires dense gas close to the source, yet the physical origin of that cocoon-like structure remains unclear. Our paper shows that late-time episodic mass-loss from supermassive stars leads to the required dense gas cocoons. After the accretion of gas into the supermassive star ends, the star contracts, ignites hydrogen burning, and re-expands into a late phase of instability. Pulsation-driven mass loss then proceeds through discrete ejection episodes that the remove weakly-bound envelope material. The earlier shells expand to large radii, whereas the final ejection remains compact and dense, setting the immediate circumstellar environment relevant to the `little red dot’ phase. The ejecta carries a characteristic abundance pattern which is consistent with spectroscopic data from the Webb telescope. The supermassive star then continues toward a General Relativistic instability and ultimately collapses into a heavy black-hole seed owing to Einstein’s gravity. Our paper examines five models with different abundances of heavy elements, all having progenitor masses of order 10⁵ solar masses. We followed the evolution of these supermassive stars after they stop accreting gas with radial pulsations calculations and general relativistic stability diagnostics. Mass loss during the final stages of evolution occurs not as a steady wind, but through discrete strange-mode ejection episodes. In the nearly pristine gas case, there were four late episodes that last 41 to 282 years and eject 10 to 348 solar masses each, for a total loss of 480 to 1,000 solar masses. The final episode alone contributes 73% of the mass-loss, and leaves behind a compact, opaque shell extending out to a light-year that reproduces the dense gas cocoons in `little red dots’. The final ejecta is dominated by hydrogen and helium but is also rich in nitrogen, as observed in `little red dots’. A supermassive star reaches the General Relativistic instability at an age of about a million years and eventually collapses within a few hours, retaining almost all of its mass. All in all, these calculations demonstrate that supermassive stars provide a physically motivated origin for the compact cocoon-like structure associated with `little red dots’, while remaining the natural progenitors of massive black hole seeds for quasars. It took 32 years to confirm my early conjecture with Fred Rasio on this subject, but the journey was definitely worthwhile. I regard 32 years as a discounted wait period. After all, according to the Old Testament, the Israelites spent 40 years wandering in the desert before reaching the promised land. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: newspaceeconomy.ca)by Konrad Szocik (1) and Abraham Loeb (2)(1) Department of Social Sciences, University of Information Technology and Management in Rzeszow, Poland; (2) Astronomy Department, Harvard University, 60 Garden Street, Cambridge MA 02138, USA (Submitted for publication in a peer-reviewed journal) Abstract Recent work on the Loeb Scale has provided astronomy a structured framework for assessing anomalous interstellar objects, including a quantitative mapping of a classification ranking, its evolution with the addition of data, and a broader observational strategy for firming its verdict. What remains unclear is the epistemic and methodological meaning of the threshold built into that framework. Here we argue that the central philosophical issue is no longer whether astronomy can define such a threshold, but how a threshold already in place should regulate scientific inquiry under uncertainty. We suggest that candidate technosignature status, such as Level 4 on the Loeb Scale, should be understood as an intermediate epistemic status: stronger than permissive openness, weaker than confirmation, yet sufficient to justify methodological escalation. The argument proceeds in three steps. First, it reconstructs the recent philosophical debate through the work of Lomas, Lane, and Cowie. Second, it turns to historical cases discussed by Kaplan (2026) to show that important discoveries are often delayed not only by weak evidence, but also by paradigms, prestige, and institutional filtering. Third, it interprets candidate status as a form of structured scientific commitment under uncertainty, one that justifies intensified observation, broader hypothesis management, and more deliberate allocation of attention and resources without licensing belief in artificial origin. The paper concludes by arguing that AI should not be the arbitrator in deducing an extraterrestrial origin, but can support the detection, comparison, and prioritization of anomalies once a candidate status has been formally recognized. Ultimately, a wealth of scientific data could identify an extraterrestrial technological signature beyond any reasonable doubt, but its availability requires a commitment by the mainstream scientific community to collect the evidence in the midst of uncertainty. Keywords: technosignatures; interstellar objects; Loeb Scale; extraterrestrial hypothesis; philosophy of science; scientific discovery; AI Introduction Debates about anomalous interstellar objects are not only about whether extraordinary hypotheses may be considered. The deeper question is when an anomaly becomes serious enough to justify a change in scientific practice. Recent philosophical work has clarified one important point: extraterrestrial-technological hypotheses should not be excluded a priori. Tim Lomas argues that the extraterrestrial hypothesis should be treated as a serious scientific possibility in light of growing institutional attention to anomalous cases, ongoing research on extraterrestrial life, and the fact that interstellar travel cannot simply be ruled out as physically impossible (Lomas, 2024). William Lane goes further and argues that the extraterrestrial hypothesis should be removed from the realm of academic taboo and treated as a rational hypothesis when case-specific evidence warrants it (Lane, 2025). These interventions challenge a reflexive dismissal that is often sociological and cultural before it becomes genuinely epistemic. Yet the permissibility of considering such hypotheses does not by itself determine when they become methodologically relevant in a particular case. Openness is a necessary condition of inquiry, but it is not, by itself, a rule of evaluation. At the same time, recent criticism of extraterrestrial-artifact interpretations has shown the opposite danger: anomalous behavior alone does not justify escalation. Christopher Cowie’s analysis of the first recognized interstellar object, 1I/‘Oumuamua, shows why weak natural explanations do not automatically warrant an extraterrestrial-artifact interpretation, since priors matter and unconceived natural alternatives remain possible (Cowie, 2023). His broader critique of optimism in the search for extraterrestrial life reinforces the same point. The abundance of planets alone does not justify confidence that life is common, technologically developed, or detectably present (Cowie, 2025). The central philosophical problem is therefore one of threshold-setting under uncertainty. The issue is not whether extraterrestrial-technological hypotheses may enter scientific discourse, but when an anomaly becomes sufficiently structured, resilient, and consequential to justify a different mode of scientific treatment. Recent work in astronomy has substantially sharpened this problem through the development of the Loeb Scale. The scale introduces a ten-level classificatory framework for interstellar objects and identifies Level 4 as the point at which technosignature indicators enter formal consideration (Eldadi et al., 2025). A quantitative mapping places Level 4 at approximately 0.60–0.70 on a continuous scale (Trivedi & Loeb, 2025b), while an evolving version extends the framework into a real-time classificatory scheme with memory, hysteresis, and predictive capacity as objects approach the inner Solar System (Trivedi & Loeb, 2025a). The proposed Comprehensive InterStellar Objects Network further links classification to a coordinated architecture of discovery, characterization, and selective interception, making the response to anomalous interstellar objects increasingly predictive rather than reactive (Trivedi & Loeb, 2026). This paper clarifies the epistemic and methodological meaning of a threshold that astronomy has already begun to formalize. More specifically, the paper argues that candidate technosignature status should be understood as an intermediate epistemic status: stronger than mere openness, weaker than confirmation, yet sufficient to justify intensified observation, broader hypothesis management, and more deliberate allocation of attention and resources aimed at clarifying the nature of an object. The change authorized by such a threshold is methodological rather than doxastic. It licenses escalation in scientific attention without licensing belief in artificial origin. Ultimately, a wealth of scientific data could identify an extraterrestrial technological signature beyond any reasonable doubt, but its availability requires a commitment by the mainstream scientific community to collect the evidence in the midst of uncertainty. Our discussion proceeds in three steps. We begin by reconstructing the recent philosophical debate through the work of Lomas, Lane, and Cowie. We then discuss historical cases considered by Kaplan (2026) to show that delayed recognition often reflects not only weak evidence, but also paradigms, institutional habits, prestige, and reputational risk. Finally, we offer an interpretation of candidate status as a structured form of scientific commitment under uncertainty and consider the role that AI may play in the large-scale detection, comparison, and prioritization of anomalous cases once such status has been formally recognized. The philosophical problem after the Loeb Scale Lomas and Lane are right to reject the reflexive disrepute historically attached to the extraterrestrial hypothesis. Lomas argues that neighboring fields of legitimate inquiry, including astrobiology, technosignature research, and interstellar propulsion, make it unreasonable to treat the hypothesis as intrinsically unscientific or methodologically suspect (Lomas, 2024). Lane makes a related point: the extraterrestrial hypothesis does not conflict with established science, need not count as extraordinary in the stronger sense often assumed by its critics, and may legitimately enter inference to the best explanation when supported by the evidence (Lane, 2025). These arguments undermine a gatekeeping model in which ridicule is mistaken for rigor. Yet removing illegitimate barriers does not by itself resolve the philosophical problem. To show that a hypothesis may be entertained is not to show when it should begin to shape inquiry. Scientific rationality requires not only admissibility, but criteria for when an anomaly warrants closer scrutiny, coordinated investigation, the allocation of resources, and a partial reordering of explanatory priorities. The central issue, then, is not whether extraterrestrial-artifact hypotheses may enter scientific discourse, but under what conditions they should acquire genuine methodological significance. Cowie’s work clarifies the opposite danger. His analysis of the 1I/‘Oumuamua debate shows why the weakness of current natural explanations does not, by itself, justify an extraterrestrial-artifact interpretation. What matters is not only the inadequacy of known alternatives, but also the prior plausibility of extraterrestrial-artifact hypotheses and the standing possibility of unconceived natural explanations (Cowie, 2023). His broader discussion of optimism in the search for extraterrestrial life reinforces the same point. One cannot move directly from the abundance of planets to warranted confidence that life is common, technologically developed, or detectably present without further assumptions (Cowie, 2025). Explanatory difficulty alone is therefore insufficient. The absence of a satisfying natural account does not automatically confer positive epistemic weight on an artificial one. The position defended in this paper lies between these two errors. Against dismissive skepticism, it rejects the view that extraterrestrial-artifact hypotheses are methodologically disreputable in principle. Against premature endorsement, it rejects the view that anomaly alone is enough to justify a shift in scientific treatment. After the formulation of the Loeb Scale in 2025, the philosophical problem is best understood as one of rational threshold-setting under uncertainty. Once a classificatory framework identifies a point at which technosignature indicators warrant formal consideration, the relevant question is no longer whether artificial origin has been established. It is whether the anomaly has become sufficiently structured and consequential to justify a change in how inquiry is organized. On this view, a threshold such as Level 4 on the Loeb Scale should be understood not as confirmation, but as the point at which an anomaly warrants a different mode of scientific response. What follows is not assent to the extraterrestrial hypothesis, but a rational shift in inquiry: intensified monitoring, broader comparison of hypotheses, greater institutional coordination, and increased willingness to sustain costly investigation. Science does not need certainty in order to escalate attention, but it does require principled criteria for when such escalation becomes justified. The Loeb Scale and the threshold problem Recent work on the Loeb Scale in 2025 has changed the philosophical landscape by turning a vague dispute about anomalous interstellar objects into a formally specified threshold problem. The issue is no longer whether one may discuss extraterrestrial-artifact hypotheses without embarrassment. It is whether astronomy has now identified a point at which such hypotheses become methodologically relevant for justifying the gathering of new data without yet becoming evidentially confirmed. The Loeb Scale provides the first explicit structure for that transition. Extending the logic of the Torino Scale to interstellar objects, it distinguishes ordinary natural cases, persistent anomalies, and upper levels reserved for confirmed artificial origin (Eldadi et al., 2025). The crucial level for the present argument is Level 4. At this rank, technosignature indicators enter formal scientific consideration, but artificial origin is not treated as established. Level 4 therefore marks neither mere openness nor confirmation, but a regulated intermediate status marked by uncertainty between them. The quantitative mapping of the Loeb Scale makes that structure more exact by translating categorical levels into a continuous score based on observable anomaly metrics, including non-gravitational acceleration, spectral or compositional anomaly, geometry or lightcurve anomaly, albedo or surface-weathering anomaly, trajectory improbability, electromagnetic signals, and operational behavior (Trivedi & Loeb, 2025b). Its significance is not that it settles the question of origin, but that it specifies when the extraterrestrial-artifact hypothesis becomes serious enough to alter the organization of inquiry (Trivedi & Loeb, 2025b). The evolving version of the scale sharpens the point further by showing that the threshold problem is temporal as well as classificatory. Because interstellar objects are typically first detected under substantial uncertainty, their significance cannot be captured adequately by a static score alone. Trivedi and Loeb therefore introduce an effective score that changes as new data accumulate, incorporating memory, hysteresis, and predictive capability (Trivedi & Loeb, 2025a). The philosophical problem is thus not simply how to classify an object at a given moment, but how inquiry should respond as an anomaly becomes progressively more structured over time. The same logic is institutionalized in the proposed Comprehensive InterStellar Objects Network (CISON). That architecture combines dual-hemisphere wide-field discovery, rapid high-resolution characterization, and selective escalation to interceptor missions, with the explicit aim of making classification predictive rather than reactive (Trivedi & Loeb, 2026). What is being constructed, then, is an emerging regime of epistemic escalation: a framework in which classification increasingly governs attention, coordination, and possible intervention. For that reason, the central philosophical question is no longer whether such a threshold can be defined. Astronomers have already begun to define it. The question is what epistemic and methodological significance should be assigned to a threshold designed to justify escalation before confirmation. Historical lessons about serious anomalies Semmelweis, Gordon, and Holmes The history of puerperal fever remains one of the clearest examples of how science can fail to recognize the significance of an anomaly. In the book “I Told You So!”, Matt Kaplan presents Ignaz Semmelweis as a case in which a strong anomaly was recognized before the accepted theoretical framework fully caught up with it (Kaplan, 2026). Semmelweis did not begin with modern germ theory. What he had was a robust and recurring pattern in hospital data: women treated by doctors in one ward died of puerperal fever at much higher rates than women treated by midwives in another. He compared cases, ruled out standard environmental explanations, and eventually connected the mortality pattern to doctors carrying infectious matter from the dissecting room to patients. When handwashing was introduced, mortality fell sharply (Kaplan, 2026). Two points are especially important here. First, the anomaly was scientifically serious before the accepted theory could fully explain it. The data outran the background theory. Second, the resistance was not merely intellectual. To accept the pattern meant accepting that physicians themselves were implicated in preventable deaths. In Kaplan’s reconstruction, the case shows how evidence can be resisted not because it is weak, but because its implications are institutionally and psychologically costly (Kaplan, 2026). Alexander Gordon and Oliver Wendell Holmes deepen the point. Kaplan presents them as earlier or parallel recognizers of the same transmission pattern. Their importance lies in showing that scientific warrant can emerge from converging cases rather than from a single decisive experiment (Kaplan, 2026). That lesson matters for anomaly research. A serious case may emerge not from one striking event, but from a stable pattern across observations. Pierre Louis and quantification Pierre Louis brings a different issue into view. His importance lies in showing how quantitative comparison can challenge established practice. Kaplan presents Louis as a figure who used numerical analysis to criticize bloodletting and other treatments that many physicians regarded as obviously effective (Kaplan, 2026). By comparing patient outcomes, he showed that long-accepted procedures often lacked the evidential support people assumed they had. The broader lesson is simple. Communities often continue to rely on what seems plausible long after more explicit methods begin to suggest otherwise. In anomaly assessment, the equivalent danger is deference to tacit expert comfort. An object may continue to be treated as ordinary not because the evidence strongly supports an ordinary explanation, but because the available procedures are too weak to discipline intuition. Schweitzer, Moyer, Karikó, and Woese Kaplan’s opening case about Mary Schweitzer and Alison Moyer provides perhaps the closest contemporary analogy to disputes over anomalous objects. Schweitzer’s work challenged the entrenched assumption that soft tissues could not survive over deep time. Moyer then challenged overly quick interpretations of fossil color evidence by asking whether structures identified as melanosomes might instead be bacterial (Kaplan, 2026). In both cases, the central issue was not only the evidence itself, but also the way professional communities react when familiar assumptions are threatened. Science can fail by dismissing anomalies too quickly, but it can also fail by stabilizing new interpretations too quickly. Katalin Karikó’s story adds an institutional dimension. Kaplan presents the mRNA case as one in which a major breakthrough was delayed not simply by lack of evidence, but by funding structures, credibility judgments, and institutional pessimism (Kaplan, 2026). Work later recognized as transformative can remain marginal for a long time because institutions tend to reward what already appears plausible. Carl Woese points to a related lesson. As Kaplan reconstructs the case, Woese’s molecular methods revealed a biological category, Archaea, that earlier classificatory frameworks had failed to identify clearly (Kaplan, 2026). This was not merely a better interpretation of familiar evidence. It depended on methods capable of making a previously unrecognized category visible. These cases matter for anomalous interstellar objects in two ways. They suggest, first, that significant anomalies may require institutional protection before confirmation. They suggest, second, that some advances depend not only on new ideas, but also on new classificatory tools and new observational methods. The epistemic meaning of candidate status The historical cases discussed above do not show that scientific standards should be relaxed. They show, rather, that standards must be better calibrated to the treatment of serious anomalies. A candidate technosignature, as understood here, is not a conclusion about the nature of an object. It is an intermediate epistemic status. It marks the point at which the technological hypothesis becomes sufficiently serious to justify organized scientific treatment alongside natural hypotheses, even though artificial origin has not been established. Candidate status is therefore weaker than confirmation, stronger than permissive openness, and more disciplined than a merely general willingness to consider all possibilities. Several features define this status. First, it is evidence-sensitive. It presupposes instrumentally robust data rather than anecdote, poor-quality imagery, or isolated reports. This requirement is central both to the Galileo Project overview and to the multimodal observational framework developed by Loeb & Laukien and Watters et al., where high-quality, traceable, multi-modal data are treated as essential for distinguishing natural, human-made, and potentially unfamiliar objects (Loeb & Laukien, 2023; Watters et al., 2023). Second, candidate status is cumulative rather than binary. The Loeb Scale and its quantitative mapping assume that anomalies may accumulate across multiple observables, and that corroboration across trajectory, spectrum, geometry, and related metrics carries more epistemic weight than any single isolated irregularity (Eldadi et al., 2025; Trivedi & Loeb, 2025b). Philosophically, this means that candidate status is justified by a convergent evidential profile rather than by one dramatic fact. Third, candidate status remains fully compatible with underdetermination. Cowie is right to insist that unconceived alternatives remain a live problem, and nothing in Level 4 on the Loeb Scale removes that difficulty (Cowie, 2023). Candidate status should therefore not be understood as closing inquiry. It is better understood as a rule for intensified investigation under persistent uncertainty. Fourth, candidate status is action-guiding. The recent Loeb Scale papers connect Level 4 and above to enhanced observational campaigns, prioritized telescope time, and increasingly coordinated responses as anomaly levels rise (Eldadi et al., 2025; Trivedi & Loeb, 2025b; Trivedi & Loeb, 2026). Its significance is therefore not merely descriptive. It concerns what forms of scientific response become rationally appropriate once a threshold has been crossed. Fifth, candidate status remains revisable. This is especially clear where the effective score changes as new data accumulate and where stable prediction depends on persistence rather than on transient spikes (Trivedi & Loeb, 2025a). Candidate status is thus best understood as a provisional but structured commitment. On this view, Level 4 on the Loeb Scale does not imply that artificial origin is probable in any strong sense. It means, rather, that the anomaly has become sufficiently serious to justify a change in scientific practice. 1I/‘Oumuamua as a test case No recent object illustrates the need for this interpretation more clearly than 1I/‘Oumuamua. The significance of the case lies precisely in the fact that it remains contested. Recent work connected a set of observed anomalies to a specific physical hypothesis — solar radiation pressure acting on an unusually thin object — and argued that a technological explanation should not be excluded in advance (Bialy & Loeb, 2018; Loeb, 2022). Critics have generally responded either by maintaining that natural explanations remain available or by arguing that the extraterrestrial-artifact hypothesis is too weakly supported, given uncertainty about priors and the standing possibility of unconceived alternatives (Cowie, 2023). Both responses are philosophically instructive. The case shows why openness matters: a sufficiently anomalous object should not be dismissed at the outset. But it also shows why candidate status must not be confused with confirmation. A significant anomaly does not eliminate the role of priors, nor does it dissolve the problem of unconceived natural alternatives. That is precisely why 1I/‘Oumuamua matters here because there are good reasons to classify it as a Level 4 object on the Loeb Scale rather than as a confirmed artifact (Eldadi et al., 2025; Trivedi & Loeb, 2025b). This is exactly the kind of judgment that requires philosophical clarification. Level 4 on the Loeb Scale does not mean that the case has been settled. It means that the anomaly is too structured and too consequential to be treated as just another unresolved natural irregularity. The familiar opposition between natural and artificial is too coarse for a case of this kind. What is needed is an intermediate category for cases that are too anomalous to dismiss, yet not sufficiently established to confirm as artificial. Artificial Intelligence (AI) and large-scale anomaly assessment The importance of candidate status becomes even clearer once one considers the likely scale of future anomaly detection. If multimodal observatories and increasingly sensitive surveys generate very large streams of data, unaided human judgment will not be sufficient to identify, compare, and prioritize anomalous cases. A basic distinction is therefore necessary. AI should not be used to determine extraterrestrial origin. That would merely automate epistemic overreach. Its proper role is methodological: to support the detection, comparison, and prioritization of anomalies under conditions of scale and complexity. That role is already implicit in the broader framework. The Galileo Project was designed around the collection of transparent, open, multi-modal data and the use of AI algorithms to distinguish familiar objects from more anomalous ones (Loeb & Laukien, 2023). Watters et al. likewise describe anomaly recognition as the identification of outlier events within a high-dimensional space constructed from multiple sensor modalities (Watters et al., 2023). In the interstellar-object context, the proposed CISON architecture extends the same logic by coupling discovery, rapid characterization, and selective escalation to the evolving Loeb Scale, so that classification becomes predictive rather than reactive (Trivedi & Loeb, 2026). There is also a useful historical parallel to Pierre Louis. Louis did not replace judgment with numbers. He used quantitative comparison to correct judgments that were overly dependent on intuition, habit, and professional convention. AI should serve a similar function in anomaly research. Properly used, it can reduce the influence of selective attention, reputational bias, and weak human pattern recognition on decisions about which anomalies deserve sustained scientific attention. This point is especially important in the case of candidate technosignatures. A common concern is that any formal candidate category might encourage sensationalism. Yet an AI-assisted anomaly pipeline could have the opposite effect. By making explicit why a case has been prioritized, which features render it anomalous, and how it compares with known classes of events, such a system could improve transparency, reproducibility, and calibration. Conclusion In the scientific assessment of anomalous interstellar objects, the key issue is not only whether extraterrestrial-technological hypotheses may be considered, nor only whether caution remains justified. It is when an anomaly becomes strong enough to warrant treatment as a candidate technosignature and motivate the collection of more data. Recent philosophical discussions have clarified two points of lasting importance. The extraterrestrial hypotheses should not be excluded a priori, but weak natural explanations do not by themselves justify extraordinary conclusions. Recent astronomical work has added something equally important: a formal framework of the Loeb Scale for classifying anomalous interstellar objects and for identifying the point at which technosignature indicators warrant systematic attention (Eldadi et al., 2025; Trivedi & Loeb, 2025a, 2025b, 2026). The contribution of the present paper is to clarify the epistemic and methodological meaning of that threshold. The historical cases considered here suggest that serious anomalies often require institutional and methodological protection before confirmation. The philosophical analysis, in turn, shows that candidate status differs both from mere openness and from final judgment. A discovery-capable science must therefore avoid two errors at once. It must not treat anomaly as proof, but neither should it suppress the significance of anomaly before that significance has been properly assessed. The aim is not to lower scientific standards, but to apply them in a way that makes serious anomalies easier to recognize, compare, and pursue. References Bialy, S., & Loeb, A. (2018). Could solar radiation pressure explain ‘Oumuamua’s peculiar acceleration? The Astrophysical Journal Letters, 868(1), L1. https://doi.org/10.3847/2041-8213/aaeda8 Cowie, C. (2023). Arguing about extraterrestrial intelligence. The Philosophical Quarterly, 73(1), 64–83. https://doi.org/10.1093/pq/pqac009 Cowie, C. (2025). Optimism in the search for extraterrestrial life? A philosophical perspective. Proceedings of the Aristotelian Society, 125(1), 44–61. https://doi.org/10.1093/arisoc/aoaf003 Eldadi, O., Tenenbaum, G., & Loeb, A. (2025). The interstellar object significance scale (Loeb Scale): Astronomical classification of interstellar objects. International Journal of Astrobiology, 24, e22. https://doi.org/10.1017/S1473550425100190 Kaplan, M. (2026). I Told You So!: Scientists Who Were Ridiculed, Exiled, and Imprisoned for Being Right. St. Martin’s Griffin. Lane, W. C. (2025). The extraterrestrial hypothesis: An epistemological case for removing the taboo. European Journal for Philosophy of Science, 15, Article 8. https://doi.org/10.1007/s13194-025-00634-8 Lingam, M., Haqq-Misra, J., Wright, J. T., Huston, M. J., Frank, A., & Kopparapu, R. (2023). Technosignatures: Frameworks for their assessment. The Astrophysical Journal, 943(1), Article 27. https://doi.org/10.3847/1538-4357/acaca0 Loeb, A. (2022). On the possibility of an artificial origin for ‘Oumuamua. Astrobiology, 22(12), 1392–1399. https://doi.org/10.1089/ast.2021.0193 Loeb, A., & Laukien, F. H. (2023). Overview of the Galileo Project. Journal of Astronomical Instrumentation, 12(1), 2340003. https://doi.org/10.1142/S2251171723400032 Lomas, T. (2024). The extraterrestrial hypothesis: A case for scientific openness to an interstellar explanation for unidentified anomalous phenomena. Philosophy and Cosmology, 32, 34–59. https://doi.org/10.29202/phil-cosm/32/3 Meech, K. J., Weryk, R., Micheli, M., Kleyna, J. T., Hainaut, O. R., Jedicke, R., Wainscoat, R. J., Chambers, K. C., Keane, J. V., Petric, A., Denneau, L., Magnier, E. A., Berger, T., Huber, M. E., Flewelling, H. A., Waters, C., Schunova-Lilly, E., & Chastel, S. (2017). A brief visit from a red and extremely elongated interstellar asteroid. Nature, 552, 378–381. https://doi.org/10.1038/nature25020 Micheli, M., Farnocchia, D., Meech, K. J., Buie, M. W., Hainaut, O. R., Prialnik, D., Schörghofer, N., Weaver, H. A., Chodas, P. W., Kleyna, J. T., Weryk, R., Wainscoat, R. J., Ebeling, H., Keane, J. V., Chambers, K. C., Koschny, D., & Petropoulos, A. E. (2018). Non-gravitational acceleration in the trajectory of 1I/2017 U1 (‘Oumuamua). Nature, 559, 223–226. https://doi.org/10.1038/s41586-018-0254-4 Trivedi, O., & Loeb, A. (2025a). Evolving the Loeb Scale [Preprint]. arXiv. https://arxiv.org/abs/2512.13743 Trivedi, O., & Loeb, A. (2025b). Quantitative mapping of the Loeb Scale [Preprint]. arXiv. https://arxiv.org/abs/2509.06253 Trivedi, O., & Loeb, A. (2026). A comprehensive network for the discovery and characterization of interstellar objects [Preprint]. arXiv. https://arxiv.org/abs/2601.21184 Watters, W. A., Loeb, A., Laukien, F., Cloete, R., Delacroix, A., Dobroshinsky, S., Horvath, B., Kelderman, E., Little, S., Masson, E., Mead, A., Randall, M., Schultz, F., Szenher, M., Vervelidou, F., White, A., Ahlstrom, A., Cleland, C., Dockal, S., Donahue, N., Elowitz, M., Ezell, C., Gersznowicz, A., Gold, N., Hercz, M. G., Keto, E. R., Knuth, K. H., Lux, A., Melnick, G. J., Moro-Martin, A., Martín-Torres, J., Llusa Ribes, D., Sail, P., Teodorani, M., Tedesco, J. J., Tedesco, G. T., Tu, M., & Zorzano, M.-P. (2023). The scientific investigation of unidentified aerial phenomena (UAP) using multimodal ground-based observatories. Journal of Astronomical Instrumentation, 12(1), 2340006. https://doi.org/10.1142/S2251171723400068 ABOUT THE MEDIUM POSTING AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: Greg Wyatt)Life on Earth started with the Last Universal Common Ancestor (LUCA), dated to 4.2 billion years ago (as deduced here). Humanity’s first artificial satellite was Sputnik, launched away from Earth’s surface on October 4, 1957. It is commonly assumed that this was the first technological satellite around Earth. However, suppose intelligent life emerged when Earth was 94% of its current age (which is 4.54 billion years), namely 272 million years ago. In that case, a technological civilization could have started launching satellites a few million years after their intelligence emerged — similarly to humanity’s case. About 252 million years ago, this 20-million-years-old civilization could have polluted the Earth’s atmosphere with greenhouse gases, enough to trigger the largest extinction in Earth’s history, ending the Permian period by killing 96% of marine species in a global warming event that left ocean animals unable to breathe. This well-known “great dying” event in Earth’s history is often interpreted as the natural consequence of the release of greenhouse gases by volcanic eruptions (as reported here). But what if this global catastrophe was technologically-driven instead? Would we have notice any “smoking gun” left in the crime scene? (Image credit: Greg Wyatt)Over the past 252 million years, surface layers of Earth have continuously mixed with the interior, primarily through plate tectonics. Subduction zones drag surface crust, water, and sediments into the mantle, while mantle plumes and volcanic activity bring interior materials to the surface. This mixing could have destroyed or buried any technological relics on Earth’s surface from that time. However, sufficiently advanced technological orbiters could have survived. Such `pre-historic’ satellites would be flagged as Unidentified Flying Objects (UFOs) by the U.S. military and intelligence agencies. The imminent release of UFO files by the White House might provide archaeological evidence for a pre-human intelligence on Earth. A more speculative idea is that humanity will develop a time machine in the future. In that case, UFOs might simply represent visits from our future. The feasibility of a time machine can only be assessed once we develop a predictive theory of quantum gravity. So far, we can only say that no Jewish scientist was able to use a time machine in our future to travel back in time and prevent the holocaust by killing Adolf Hitler. I would have certainly entered such a machine, because 65 members of my father’s family were killed in Nazi concentration camps. They were naïve enough to believe that German patriotism would save them from the Nazi gas chambers. My grandfather, Albert Loeb — after whom I am named, was wise enough to leave Germany in 1936. He did not count on a time machine to correct the political miscalculation of his family members. (Image credit: Greg Wyatt)The most likely interpretation of UFO videos, to be released by the White House shortly, is that they reflect natural or human-made objects that were misidentified by the Pentagon or intelligence agencies out of confusion, by associating independent objects as a single fast-moving object, or being misguided by optical illusions or incorrect assessments of distances to objects or motion of the camera. Nevertheless, if the data is good enough it could potentially flag outliers outside the performance envelope of human-made technologies — in which case these might be products of extraterrestrial technological civilizations. Such objects would be a matter of planetary defense rather than national security, because all nations are passengers in the same boat. As soon as the UFO videos, never-seen-before by the public, will be released on the website aliens.gov, I plan to analyze them with the research team of the Galileo Project and share our preliminary assessments with the public. The question of whether non-human-made technological objects are lurking in the sky is not a matter of opinion or belief. It should be answered by scientific data analysis. And if the existing data is not good enough, we should collect more data with better sensors. This is the goal of the Galileo Project under my leadership. We do not need to rely on the government telling us what lies in the sky. Instead, we look up and figure it out ourselves. (Image credit: Greg Wyatt)*** Below is the transcript of a related interview that I had this morning with the anchors Marc Lotter (ML) and Sharla McBride (SM) on “Wake Up America.” The video version of this interview is accessible here. (Image credit: Newsmax)ML: Welcome back to Wake Up America. So, if you haven’t had enough space talk after NASA’s Artemis II moon mission, President Trump is now promising to break open the vaults when it comes to UFOs; take a listen: “This process is well underway and we found many very interesting documents, I must say. And the first releases will begin very, very soon. So, you can go out and see if the phenomena are correct. You’ll figure it out. Let me know.” So as lawmakers demand the release of America’s UFO files, the president’s announcement leaves many Americans, including me, once again questioning the government’s knowledge of potential alien life. And joining us now to break it all down, astrophysicist, Harvard University professor, Dr. Avi Loeb. So good morning, Professor. President Trump ordered the Pentagon to begin reviewing these files related to aliens and UAPs back in February. What are you thinking? Are we actually going to see anything that we don’t already know? AL: On Friday, I had the fortune of a visit by Congresswoman Anna Paulina Luna to my office. We spoke for about 90 minutes, and it definitely looks like there are objects that either the intelligence agencies or the Pentagon cannot figure out, and that’s what makes life interesting. The Trump administration rejuvenated space exploration with the Artemis II success recently. They’re also pursuing the new age of artificial intelligence. But I’m most interested in whether we have neighbors, whether there is alien intelligence, because that could transform the future of humanity. Obviously, the government has a lot of data, which in part will be declassified and released, while other data will stay hidden from view because it relates to classified sensors or touches on national security. So, we will not see everything. The question is whether we will see some interesting data coming out in the first release on aliens.gov — the website that is currently expected to be the one where all the data will be deposited. SM: I like that you are referring to them as neighbors. That’s nice. That’s a nice way to look at things. So, when UFO sightings have been reported in this country in the past, the military has been quick to kind of swoop in and ensure that there are no national security threats. And since the government has mostly kept what they found from secret sightings secret, how much do you think will still be redacted when these files are released? AL: I expect only parts that relate to national security to be redacted or not released at all. But the disclosed data is really something that all of us should have a look at, especially scientists like myself. I am leading the Galileo Project, where we are looking up. We don’t just wait for the government to tell us what is out there in the sky, because we can build telescopes and observe it. And we are analyzing our data with machine learning or artificial intelligence. I just told my research team yesterday that once the data is released on the new government website, we must immediately examine it and assess what it implies. It may well be related to mundane phenomena or to human-made technologies. So, we have to look at it. It’s all about the data. It’s not a matter of belief or conviction or opinion. It’s all about looking at the data and seeing what it means. And very often you don’t know the distance of objects or two objects may appear as the same object, so you can’t tell how fast they are moving. In the Galileo project, we use triangulation to figure out distances, accelerations, velocities, and we are still searching for something that is not human-made. Anything human-made is boring as far as I’m concerned. ML: So, Professor, here’s my problem, and trust me, I believe that we are not alone, or space would be an awful waste of space, but I can prove one thing: the government in Washington leaks like the Titanic, and if they have had information, I have to believe someone would have leaked it to the media in the last 70-plus years. A: I agree with you. The most reasonable scenario that I can imagine is there are things that the government cannot figure out. The intelligence agencies and the Pentagon prefer to keep these things under wraps in order not to be embarrassed that they’re not doing their job. Also, some of this data relates to classified censors, so they would not release it in order for adversarial nations not to be aware of our capabilities. The way I see it, is that there is something that they do not understand. And I am here to help them figure it out. At the very least, it will help national security. We will feel safer. Remember the Chinese spy balloon incident where it took a while before it was spotted and eventually shot down. At the very least, this would help the Pentagon and the Intelligence agencies to do their job. But if we find that we are not alone, that would be the biggest revelation ever made. And I think it will bring us to a better place. ML: Well, let me tell you, having worked for decades in the government, there’s a lot they don’t understand. Dr. Avi Loeb, thank you very much. Appreciate the conversation. *** In this essay, I featured four amazing watercolors from a series created by the celebrated artist, Greg Wyatt. These watercolors incorporate inspiring statements by Ludwig Van Beethoven, John Milton and Walt Whitman. This is the 12th in a sequence of essays, where Greg and I collaborate on the interface between art and science. The first essay in this series, titled “Music of the Cosmic Spheres,” appeared here; the second essay, titled: “Cosmic Waterfalls in Spacetime Cliffs,” appeared here; the third titled “Missing Elements in the Cosmic Jigsaw Puzzle,” appeared here; the fourth essay, titled: “Why Do We Exist?”, appeared here, and the fifth titled “Inspiration from the Stars”, appeared here, the sixth titled: “We Might Understand How the Cosmos Works Before We Understand How Life Works”, appeared here, the seventh titled: “Will the Human Survive for Billions of Years”, appeared here, the eight titled: “The Butterfly Effect of Intelligence in the Cosmos”, appeared here, the ninth titled: “Benefits of Extraterrestrial Intelligence over AI”, appeared here, the tenth titled: “Übermenschen on Exoplanets” appeared here, and the eleventh titled: “If You Had an Infinite Research Budget, How Would You Allocate It?” appeared here. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: NewsNation)Yesterday, President Trump announced in a speech, accessible here, that the first releases of the UFO files will be coming out very soon. Below is a transcript of a new interview I had last midnight on the Jesse Weber Live of NewsNation, available in video form here. Jesse’s questions are marked with JW, and my answers with AL, respectively. *** JW: After New developments in a growing showdown over UFO secrets and what the government may be holding back. A top House lawmaker demanding answers right now after the Pentagon apparently missed a Tuesday deadline to turn over 46 classified UFO videos. And the footage spanning the globe reportedly shows tic-tac-like objects over war zones near U.S. bases inside restricted airspace. And this includes a 2023 incident where an F-16 reportedly shot down an unknown flying object over Lake Huron. The Pentagon has said that its UFO office is working with the White House and other agencies to consolidate records and, quote, facilitate the expeditious release of never-before-seen UAP information. President Trump also promising the release will happen. Here’s what he told the crowd in Phoenix today: “I recently directed the Secretary of War. How good is Pete Hegseth doing? It’s related to UFOs and unexplained aerial phenomena. And I figured this was a good crowd for this because I know people. You’re really into that. So, I’m pleased to report today. I thought I’d save it for this crowd because you’re a little bit out there. That this process is well underway and we found many very interesting documents i must say and the first releases will begin very very soon.” But there’s no clear timeline, and obviously there are questions about whether there is a disclosure, whether there’s a delay. Representative Anna Paulina Luna, the chair of the task force for the declassification of federal secrets, says she is prepared to issue a subpoena to force those videos out into the open. Earlier today, she met with Harvard astrophysicist Avi Loeb, who joins me now. Good to see you, sir. So, you met with Representative Luna today (as described here). What did she tell you? I mean, is she confident that the files are going to be released soon? AL: It was an interesting discussion. Among many other things, I described with my team the latest developments in the Galileo project that I’m leading, where we monitor the sky. We are seeing millions of objects. We are trying to figure out whether any of them is an outlier relative to human-made technologies. We don’t just need to wait for the U.S. government to tell us what’s in the sky. We can look up and use the best sensors, the best artificial intelligence algorithms. So that’s the part that I related to her. And, of course, she is trying to push for the release of data from government. Now, we don’t know exactly what the data entails. Some of it was never seen before outside government. Based on conversations I had with the All-Domain Anomaly Resolution Office in the Pentagon, there may be some data within the FBI that could be quite interesting. That’s what they told me a year ago. And that is, of course, a completely different matter than classified military data. JW: Are we ready for this? Why do I say that? Representative Tim Burchett said if the public saw the things he’s been briefed on, it would keep us up at night worrying about it. Is something going on here where there’s a concern that we might not be able to handle it? AL: I don’t think that’s a valid concern. I know that Representative Luna, along with Representative Tim Burchett were shown some materials. And she also describes it as very puzzling and intriguing. And I really am looking forward to seeing it so that I can analyze it with the scientific tools that I have. Because after all, you know, it’s not a matter of belief or conviction or impression or opinion. It’s just a matter of looking at the data and figuring it out. These are objects in the physical reality that we all share and we should be able to figure them out or at least say that they are not human. JW: Is that what it is? Is it actual beings or is it spacecraft? Is it aircraft that is the concern and what you’re hearing from Representatives Burchett and Luna? AL: Ss far as I know, we are dealing with objects that cannot be easily understood. And there is no evidence, as far as I heard, for any beings. Of course, we heard the testimony from David Grush about it, but I haven’t seen any thread of evidence leading to that. And also, I asked the All-Domain Anomaly Resolution Office representatives, and they claim that they haven’t seen anything related and they have access to all information within government. Now, it’s also possible that this is compartmentalized, that different parts within government, or in fact, some of it might be within corporations like Lockheed Martin that we don’t have access to. So, this could take a while for us to see everything. JW: So in other words, you’re saying it could be red tape, not a cover-up. AL: I don’t think the government would keep a secret for so long knowing what these objects are. I think the reason that some of this information is not released is primarily because intelligence officers or military personnel prefer not to be embarrassed about not figuring out what’s in the sky. They’re getting paid to do that. And in addition, some of it is classified because the data was collected by classified sensors. That’s fair. So there are many, many reasons for keeping it the wraps. But I think it’s really important. for scientists to look into it and the public to be aware of what it means. JW: All right. We will wait and see. Avi Loeb, thank you so much. Good seeing you. Have a great weekend. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

An Inspiring Visit of Congresswoman Anna Paulina Luna to Avi Loeb’s Office at the Harvard College Observatory(Image credit: Devesh Nandal)After sitting together side-to-side on the `observers seat’ of the historical Great Refractor telescope from 1843, congresswoman Anna Paulina Luna and I walked around the display of the women “computers” of the Harvard College Observatory who pioneered major discoveries in Astronomy over a century ago. They included Henrietta Swan Leavitt, who discovered the luminosity-period relation of pulsating Cepheid stars. Measuring the pulsation period of these stars allowed to determine their distance, just like reading off the label of a 100-Watt light bulb and knowing how far the bulb is based on its observed brightness. This, in turn, enabled Edwin Hubble a century ago to measure the proportionality constant between the recession speed of distant galaxies and their distance, implying that the Universe is expanding and that it started in a Big Bang. The inverse of the Hubble constant provides an estimate for how long ago all galaxies were on top of each other, namely the age of the Universe. (Image credit: Devesh Nandal)This tour was the conclusion of a 90-minute visit by Representative Luna and her affiliates to my office at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. A few minutes before she entered the building, the Harvard police officer who escorted her told me that he is a great supporter of Representative Luna and that his son works for the Trump administration. The meeting in my office included presentations of the latest experimental results from the Galileo Project, a scientific search for extraterrestrial technological artifacts near Earth. Congresswoman Luna leads the congressional Task Force on the Declassification of Federal Secrets, and requested recently from the Pentagon the delivery of 46 specific videos of Unidentified Anomalous Phenomena (UAP). This followed on President Trump’s directive (posted here by the White House): (Image credit: Devesh Nandal)Representative Luna’s visit started with a demonstration by the Galileo Project’s chief engineer, Alex Delacroix, of the hardware used by the Galileo Project in the form of a set of infrared and visible cameras on a hemisphere, resembling R2-D2 from Star Wars, which monitor the entire sky at all times. The three Galileo Observatories in Massachusetts, Pennsylvania and Nevada are collecting data on millions of objects in the sky. The latest observatory in Las Vegas includes three units separated by 10 kilometers, one of which is top of Sphere, the largest entertainment center in the world. By observing objects in the sky from three different directions, the Galileo research team is able to validate their existence and infer their distance via the method of triangulation. This allows us to measure the altitude, velocity and acceleration of objects and search for outliers which deviate from the performance envelope of human-made technologies. The Galileo data analysts, Dr. Regina Sarmiento and Dr. Richard Cloete, presented the latest analysis tools and AI algorithms that search for these outliers. Representative Luna promised to help us engage the public in identifying the ground truth on which we train our AI models (as solicited here). (Image credit: Devesh Nandal)Finally, the renowned geochemist Professor Stein Jacobsen, who owns a home in Representative Luna’s district in Florida, and his research assistant, Dr. Eugenia Hyung, presented our latest results for the analysis of the materials retrieved from a 2023 expedition that I led to the site of the first recognized interstellar meteor in the Pacific Ocean. The meteor’s fireball was spotted by U.S. government satellites on January 8, 2014, and its interstellar origin was validated by the U.S. Space Command in an official letter to NASA (available here), following my request through the White House. About a tenth of the 850 meteoritic fragments found in the expedition had an unusual chemical and isotopic composition, indicating with a high statistical significance an origin from outside the solar system. This is the first time that materials from a massive interstellar object were analyzed in the laboratory. The same approach can be used to test any material that is alleged to have originated from outside the Solar System. Our laboratory instruments require less than a gram of any such material in order to validate or rule out its interstellar origin. At the end of the inspiring visit, I gave Representative Luna my book, titled “Interstellar,” which I dedicated to her with the words: “You are a brilliant star that illuminates the darkness we live through.” (Image credit: Devesh Nandal)Shortly after the visit ended, President Trump announced that the government UFO files will be coming out of the White House very soon (as reported here). Yesterday, I was asked for my opinion on the White House release of files (accessible here) as well as for my review of the recent movie “Project Hail Mary” (accessible here). At the end, I noted that life is a learning experience and exploring the unknown is what makes it worthwhile. Here’s hoping that we will learn intriguing facts from the White House release of the UFO files. I look forward to applying all the scientific knowledge that I acquired during my academic career over the past 46 years to the interpretation of these files. Whether we are alone or being visited is not a matter of opinion or belief. It must be derived from data. Irrespective of what we learn from the upcoming disclosure, one thing is already known from my expedition to the Pacific Ocean: the training data set offered by the Universe at large is much larger than what is available to us on Earth. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

The symmetric system of three jets emanating from the nucleus of the interstellar object 3I/ATLAS (separately from the primary anti-tail jet) after the circularly symmetric glow was removed by the Larson-Sekanina rotational gradient filter, based on a Hubble Space Telescope image taken on November 30, 2025. (Image credit: T. Scarmato and A. Loeb 2026)A new paper (accessible here) that I co-authored today with Toni Scarmato analyzed images of the interstellar object 3I/ATLAS, taken by the Hubble Space Telescope over the past five months. After removing the circularly-symmetric glow around the nucleus of 3I/ATLAS using the Larson-Sekanina rotational gradient filter, we identified three jets emanating from the nucleus that are equally separated from each other in sky projection by about 120 degrees in addition to a primary anti-tail jet pointed at the Sun. Whether these jets are technological thrusters or pockets of ice that happened to be oriented symmetrically on the surface of a natural iceberg, the outflows of gas and dust in these three jets exerted thrusts through the rocket effect, which resulted in the observed non-gravitational acceleration of 3I/ATLAS (as summarized in a paper that I co-authored with Valentin Thoss and Andi Burkert, accessible here). Our new paper links, for the first time, the directions and momentum flows in these three jets to the non-gravitational acceleration of 3I/ATLAS. In our previous paper (accessible here), we demonstrated that the jet system wobbles with a period of 7.2 hours, likely as a result the rotation of the nucleus. We concluded that the jet structure wobbles around the rotation axis with a characteristic angular excursion of about 20 degrees, and the rotation axis is aligned with the sunward direction to within about 20 degrees. Building on this inferred jet system and periodic wobble analysis of 3I/ATLAS, our new paper measures the observed jet position angles and links them to the non-gravitational acceleration components in three dimensions. We use the sky projection and images of the three persistent jets to estimate the order-of-magnitude thrust that each of them provides to the nucleus. Altogether, our analysis provides consistency between the properties of the three jets and the inferred non-gravitational acceleration of 3I/ATLAS, strengthening the evidence that the rocket effect explains the deviations of its trajectory from the path expected from gravity alone. We adopted the observed jet position angles (PAs) in the sky (with North=0◦, East=90◦) on November 30, 2025 as follows: • Jet1: PA = 65◦, • Jet2: PA = 290◦, • Jet3: PA = 175◦. Our analysis identifies Jet2 as the dominant contributor to the transverse non-gravitational acceleration. The table below shows the breakdown of the contributions from the three jets to the non-gravitational acceleration of 3I/ATLAS, a [with components (A1,A2,A3)], in meters per second squared: The complete set of Hubble Space Telescope (HST) images is available here. The symmetric configuration of three jets plus the anti-tail jet raises the question of whether they might constitute a technological system designed for stabilizing the trajectory of 3I/ATLAS. A recent paper by Bo Andree (accessible here) suggested that the minimal approach for steering an interstellar comet along a controlled trajectory indeed matches this 3+1 jet configuration. By relaxing the full six-degree-of-freedom control to forward-cone steering — sufficient for practical navigation — the paper showed that four thrusters are required: one primary jet and three secondary jets separated symmetrically by 120 degrees from each other. The secondary 3-jets synthesize continuous in-plane steering, while the primary (anti-tail) jet provides low-bandwidth attitude shaping: as the body rotates, the primary-jet torque direction sweeps predictably over a cycle, enabling out-of-plane steering via phase-scheduled firing. This highlights the fundamental question: is the observed 3+1 jet system around 3I/ATLAS a technological signature? ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: NBC News)In a recent meeting of the Galileo Project research team, my brilliant postdoc, Regina Sarmiento, presented new triangulation analysis that indicated weird zig-zag motion of an object at a distance of 5.6 kilometers. Regina dismissed this motion as unreal and moved on to discuss other objects, but I chose to stop her and said to the entire team: “when we notice a weird behavior, we should be intrigued to study it further, not to dismiss it, because the goal of the Galileo Project is to search for technological objects near Earth that were not human-made and might therefore behave weirdly.” The Galileo team immediately drilled deeper and found that the zig-zag motion represented malfunction of the triangulation software during periods where data from the cameras was absent. Regina was correct in her intuitive guess but we had to verify that she was right. Science is based on the meticulous analysis of instrument data that is openly available to scrutiny. Following President Trump’s directive in February 19, 2026 (posted here), congresswoman Anna Paulina Luna submitted a letter (accessible here) to the Secretary of War on behalf of the congressional Task Force on the Declassification of Federal Secrets, requesting the delivery of 46 specific videos of Unidentified Anomalous Phenomena (UAP) by April 14, 2026. After the deadline has passed without UAP data delivery, Luna tweeted here: “No one from the Pentagon had responded until we reached out, and it appears that someone did not pass the letter to the appropriate authorities. How convenient. Nonetheless, we will be getting the requested list. We are not waiting for a briefing at some unspecified future date.” It was subsequently confirmed by a War Department official (as reported here) that the White House is coordinating with the All Domain Anomaly Resolution Office (AARO) in the Pentagon and other federal agencies the release of new UAP data that was never publicly released before. The fundamental question is how scientifically intriguing will the released data be, and will it include the most tantalizing evidence in possession of the U.S. government. Most likely, the best data was collected recently by classified state-of-the-art sensors and therefore cannot be released for national security reasons. Personally, I had no access to classified UAP videos but my hope is that the disclosed material will be in the form of original data with no degradation or post-processing, so that scientists like myself can dig into it and help government figure out whether they have mundane or exciting interpretations. Any data from satellite imaging would be particularly interesting because it avoids ambiguities about the motion and distance of the camera relative to the objects of interest. When anomalies are documented by trustworthy intelligence officers and military personnel, mainstream scientists should be curious to investigate what these anomalies mean. Determining the nature of UAP is important for national security as it may indicate advanced technologies developed by adversarial nations. Even if the interpretation turns out to be mundane, studying the evidence is never a waste of time. It strengthens the ability of the Pentagon and the intelligence agencies to protect our nation. If in addition to videos, materials were recovered from alleged crash sites of UAP, it would be straightforward to test whether they originated beyond the solar system. Even a gram of material is sufficient for isotope analysis using a mass spectrometer. All materials in our solar system formed from the same gas cloud. Materials from another star would likely exhibit different isotopic fingerprints. Scientists like myself can help the White House and Congress determine the nature of the UAP. Disclosure does not necessarily infringe on national security. Decades-old information is unlikely to be relevant to today’s battlefield technologies since human-made systems have advanced dramatically since then. Data on UAP outside the performance envelope of human-made technologies should be scrutinized for mundane interpretations like malfunction of the sensors or the analysis software. Detection by multiple sensors that are separated from each other would allow triangulation and verification. We must know whether we have a cosmic neighbor. Finding evidence for it would transform our current perception of the Universe as a cold and lonely expanse of matter and radiation which follow the laws of physics deterministically. Finding technology or science beyond our own would present us with an opportunity to learn and advance. We are living in exciting times when space exploration was recently rejuvenated by the success of the Artemis II mission and artificial intelligence (AI) is about to exceed human intelligence. But discovering alien intelligence would have far greater consequences to our future than either of these two. Alien intelligence is superior to AI in that that its training data sets exceeds what is accessible on Earth. *** Before my morning jog at sunrise, I received the following inspiring message from the poet Alan Wagstaff in New Zealand: “Dear Dr Loeb The poem, ‘Dumbfounded’ began while singing ‘When the Ship Comes In’ *, the prophetic ballad written by Bob Dylan in 1963 [a year after you were born]. In that song, “the ship” arrives as a symbol of moral reckoning and historical reversal. As I sang the image shifted in my imagination. The vessel that approached was no longer maritime — but interstellar. ‘Dumbfounded’ explores what might happen if an apparently inert astronomical object — something first dismissed as a comet or asteroid — revealed itself to be an extraterrestrial craft. This is n imaginative reflection on your oft-stated scientific inquiry. The third stanza acknowledges your influence. The final stanza turns inward, suggesting that observation itself is never neutral. In that sense, the poem is not only about first contact; it is about the difficulty of recognizing it when it arrives. To see my poem on YouTube, click on the link: https://youtu.be/r99QAlxLTjA Kind regards Alan Alan Wagstaff New Zealand When the Ship Comes Inhttps://www.youtube.com/watch?v=fHmQadd0FkA&list=RDfHmQadd0FkA&start_radio=1 Oh a time will come up when the winds will stop and the breeze will cease to be a -breathin’. Like the stillness in the wind before the hurricane begins, hour that the ship comes in. And the sea will split and the ships will hit. And the sands on the shoreline will be shaking. And the tide will sound and the waves will pound, and the morning will be breaking. Oh the fishes will laugh as they swim out of the path And the seagulls they’ll be a-smilin’ And the rocks on the sand will proudly stand The hour that the ship comes in And the words that are used for to get the ship confused Will not be understood as they’re spoken Oh the chains of the sea will have busted in the night And be buried on the bottom of the ocean. A song will lift as the main sail shifts And the boat drifts unto the shoreline And the sun will respect every face on the deck The hour that the ship comes in And the sands will roll out a carpet of gold For your wearied toes to be a-touchin’ And the ship’s wise men will remind you once again That the whole wide world is watchin’. Oh the foe will arise with the sleep still in their eyes And they’ll jerk from their beds and think they’re dreamin’ But they’ll pinch themselves and squeal And they’ll know that it’s for real, The hour that the ship comes in And they’ll raise their hands Sayin’ we’ll meet all you demands But we’ll shout from the bow Your days are numbered And like Pharoah’s tribe they’ll be drowned in the tide And like Goliath they’ll be conquered Bob Dylan 1963” ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

In his seminal work Astronomia Nova (1609), Johannes Kepler commented on the mutual gravitational attraction between the Moon and Earth. 417 years later, the Artemis II crew circled the Moon and returned to Earth, sampling the gravitational potential wells of the two bodies. The cost was 4.1 billion dollars. What would NASA do with an infinite budget? (Image credit: Greg Wyatt)Today I was asked by students: “If you had an infinite research budget, how would you allocate it?” This is an interesting question to be asked just a week after the White House released the FY2027 Budget Request with major proposed cuts to science agencies. Cutting fundamental science while nurturing the latest technological advances is equivalent to cutting the roots of a tree and hoping that watering its leaves will keep the tree alive. Investment in fundamental science reflects hopes for new discoveries with major implications to society. The silicon chips used to facilitate the advanced technology of artificial intelligence systems were enabled by fundamental research on quantum mechanics and solid-state physics over the past century. How could we maximally promote future breakthroughs with an infinite research budget? The answer depends on imagination. But the imagination of both natural and artificial intelligence is limited to content found so far on planet Earth or its immediate vicinity. We know that we are missing a lot about the cosmos at large because we have not identified 95% of the cosmic mass budget. We encapsulate our ignorance by using the labels `dark matter’ and `dark energy’. These are examples for `known unknowns.’ But our ignorance might be much bigger as a result of `unknown unknowns.’ How can we discover them with additional research funds? (Image credit: Greg Wyatt)The answer is straightforward. We should attempt to maximize the disruptive discovery of `unknown unknowns.’ Currently, all research funds are allocated to studying either `known knowns’ or `known unknowns.’ How can we seek the `unknown unknowns’ if we have no clue as to what they are? As with the search for the nature of `dark matter’ and `dark energy,’ the simplest approach to promoting breakthroughs is to search for anomalies, namely phenomena that do not line up with expectations. Scientists tend to sweep anomalies under the rug of traditional thinking by either assigning familiar labels to them — like `matter’ or `energy’ for invisible cosmic constituents that may otherwise reflect modified gravity, or by quenching attention to anomalies because: “Strange things happen but that does not imply that they mean anything.” Suppressing our childlike curiosity by pretending to be the adult in the room is a common strategy for avoiding reputational risks and denying the interest in a new perception of reality. (Image credit: Greg Wyatt)Consider the following example. If a space object near Earth, like the interstellar object 1I/`Oumuamua, displays a non-gravitational acceleration without a traditional cometary tail of dust or gas, it is classified as a `dark comet’ (as done here), unless it follows the trajectory of as an object launched by NASA or SpaceX (as described here and here). Just as the labels of `dark matter’ and `dark energy’ ignore the possibility of modified gravity, the label `dark comet’ ignores the possibility of an extraterrestrial technological object. To counteract this bias, my imagined research program with its infinite funding, will catalog such an object as `anomalous’ and aim to collect more data that in an attempt to explain why the object deviates from the behavior of familiar asteroids or comets. By labeling anomalous objects as `dark comets,’ dogmatists are weakening the motivation of their colleagues to fund the quest for more data on them. In this way, they are locking their opinion into a self-fulfilling prophecy where no data will be collected to falsify their prejudice. The benefit of an infinite budget is that it allows to break self-confirmation biases and circular arguments of dogmatists who control fund allocation in the current system. Unlimited research funds are essential for exploring uncharted territories beyond the beaten path and discovering the `unknown unknowns’ there. The prescription for breakthroughs is straightforward: take anomalies seriously and study non-traditional interpretations. Outliers that appear differently than expected should be pursued, not dismissed. For them to be regarded as `unknown unknowns,’ they must be distinguished from `known knowns’ and `known unknowns.’ The more data the better in promoting a new perception of reality. An experimental path for the discovery of `unknown unknowns’ involves sensors with new capabilities. For example, gravitational wave detectors allow the detection of invisible objects which do not produce or reflect light and hence escape detection by traditional telescopes. Known members of this invisible class include black holes or dark matter objects. But other types may include dark objects that make a negligible contribution to the cosmic mass budget, such as a stealth alien spacecraft passing near Earth. Similarly, cameras with a high shutter speed on telescopes with large collecting areas, would detect new fast-moving objects which currently appear as faint streaks that are ignored in existing sky surveys. On the data processing front, our discovery potential could also be expanded by employing artificial superhuman intelligence (ASI). Such ASI systems might identify patterns in large datasets that the human brain misses, and pick up new anomalies that would unravel `unknown unknowns.’ Science is guided by evidence, but scientific innovation rests on imagining which experiments are worth investing resources in. Currently, the mainstream of the astronomy community defined the search for biological signatures of microbes as its highest priority (as summarized here), worthy of investing over ten billion dollars over the next two decades. With an infinite budget, I would also invest a similar amount of money in the search for alien technological signatures, such as anomalies in interstellar objects (as discussed here), artificial lights or excess heat on the nightside of habitable exoplanets (as discussed here), or industrial pollution in exoplanet atmospheres (as discussed here). The infinite funds will support data collection on technological civilizations that exhibit similar signals that the ones we produce. In addition, ASI could also expand the limits of our imagination, by conceiving of possibilities that the human brain fails to recognize. Imagining the unknown may stem from a higher processing rate of all possibilities, reminiscent of chess playing, which allows ASI to navigate through all that is possible based on our full body of knowledge. The faster processing rate may enable ASI to imagine the unknown better than the human brain. Ultimately, what we learn about the physical reality will rely on experimental data. And as long as we develop new sensors, our research endeavor with ASI could harvest `unknown unknowns.’ In summary, if I had an infinite research budget, I would invest it in building new sensors and employing ASI to identify new anomalies in their experimental data. My research program would focus on the fingerprints of `unknown unknowns,’ which serve as rose petals leading the way to our future scientific breakthroughs. (Image credit: Greg Wyatt)Our current scientific knowledge is an island in an infinite ocean of ignorance. As we expand the landmass of this island, we increase our shoreline with the ocean of ignorance, allowing new opportunities to expand it further. Science should be viewed as an infinite-sum learning experience rather than a zero-sum game. This is my dream for how to spend an infinite research budget. And of course, with a limited budget I would pursue the same goals at a slower rate. The appearance of a rare bird in my backyard today was an anomaly of natural origin. (Image credit: Avi Loeb)*** In this essay, I featured four amazing watercolors from a series created by the celebrated artist, Greg Wyatt. These watercolors incorporate inspiring statements by John Milton and Johannes Kepler. This is the eleventh in a sequence of essays, where Greg and I collaborate on the interface between art and science. The first essay in this series, titled “Music of the Cosmic Spheres,” appeared here; the second essay, titled: “Cosmic Waterfalls in Spacetime Cliffs,” appeared here; the third titled “Missing Elements in the Cosmic Jigsaw Puzzle,” appeared here; the fourth essay, titled: “Why Do We Exist?”, appeared here, and the fifth titled “Inspiration from the Stars”, appeared here, the sixth titled: “We Might Understand How the Cosmos Works Before We Understand How Life Works”, appeared here, the seventh titled: “Will the Human Survive for Billions of Years”, appeared here, the eight titled: “The Butterfly Effect of Intelligence in the Cosmos”, appeared here, the ninth titled: “Benefits of Extraterrestrial Intelligence over AI”, appeared here, and the tenth titled: “Übermenschen on Exoplanets” appeared here. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: Getty Images/HISTORY Channel)Below is the transcript of a Questions and Answers session that I had on April 13, 2026 with a class full of students in Sweden, taught by Professor Henrik Nordvall. *** Q: First, we will give you the chance to say a few words about yourself. A: I haven’t changed much since I was a small child. I grew up on a farm and was interested mainly in nature. That’s pretty much what I am right now. I don’t care how many likes I get on social media, and my main focus is in trying to understand our cosmic environment, nature, without any prejudice, without assuming that we are at the top of the food chain. Q: The first question relates to methods and technology and research practice. It’s kind of an umbrella category: which practical and methodological challenges are the most decisive when conducting research on unidentified phenomena, such as in the Galileo Project? A: The most important thing is to pay attention to anomalies, which are behaviors that do not line up with what we expect. And you might say, well, it’s obvious if there is something that we don’t expect. Everyone would be curious to know what it is, but that’s not the case. If you spend some time in academia, what you would find is that most scientists worry about their reputation. They do not want to take risks. And they often build their stature and self-esteem on past knowledge. So, they know that every object in the sky must be either a rock or an iceberg, an asteroid or a comet. And so, as a result of that, even if the object does not behave like a rock, they would say, well, it’s a dark comet. It’s a rock of a type that we’ve never seen before, but it’s still a rock. Now, I should say it’s not just the problem of comet experts. It’s also true of any branch of science including fundamental physics or cosmology, because right now we don’t know what 95% of the content of the universe is. We give it a name; we call it dark matter. This is matter that is invisible. We call it dark energy. This is energy that is invisible. We have no idea what it is. Both of these. And, you know, for the past century or so, we’ve been searching for clues that will tell us what it is, but we call it matter and energy. Why do we label it matter and energy? Because then we feel comfortable that we pretty much understand what these things are. They’re just a different form of matter, a different form of energy. But just think about these names. It may be neither of these. It may be just modified gravity. It may well be that the way we describe gravity, Einstein’s theory of gravity, is incomplete. And because of that, we have these ghosts. We believe that there are dark matter and dark energy, even though it’s just a modified form of gravity. We use equations that are not adequate, and therefore we infer these additional components. But we haven’t found what they are. So, by labeling these components as matter and energy, cosmologies feel comfortable and then they don’t even consider seriously the possibility of modified gravity. And for the same reason, when the 1st interstellar object, `Oumuamua, was identified, it was cataloged as a `dark comet’ because it showed non-gravitational acceleration but there was no gas or dust around it. So, they called it a dark comet because the typical signature of a comet, which is a tale of gas and dust, was not found. So, instead of saying this is an anomalous object, they said it’s a dark comet. So, you can see how scientists cheat. You might say scientists should be curious and therefore when they see something that doesn’t line up with what they expect, they would immediately flag it and study it and try to figure out what it is. But no, the way they think about it is they already know the answer. It’s a comet. We don’t see evidence for a comet and so we call it a dark comet. It’s matter, we don’t see evidence for that matter, we call it dark matter. And the same with dark energy. And this is a trick being used for decades by mainstream scientists to indicate that it’s not a crisis. In fact, people get a Nobel Prize for identifying how much dark matter and how much dark energy are needed, just for doing the counting and saying how much are we missing. They get a Nobel Prize, and everyone says: “Wow, look at that. Such an accomplishment in cosmology. We had figured out how much dark matter exists. But we don’t know what it is. That’s the truth. So, the point of the kind of research that I’m doing is to stay honest. If we see an anomaly, what it should do is trigger an interest in collecting more data about it so that we can figure it out. That’s the only way to gain new knowledge. It’s not by giving names to unknown things. If you call a zebra an elephant, you don’t make it an elephant. You just gave it a name of something that it’s not. The key is to make progress in our knowledge by collecting data. That’s the only way we can make progress. And that’s the approach that I’m taking with the Galileo Project. And by the way, if I had an infinite amount of money, I would allocate it to studying anomalies and doing the best I can to figure out their nature. So that’s basically the approach that I’m taking. Q: Right. I have a couple of questions that that are connected to this. What kinds of evidence would lead you to consider an object such as an asteroid or a comet fragment as being a possible techno signature? And what broader scientific questions, could such a discovery help answer? A: If I had the the ability to collect the best data possible, then obviously there is a very simple thing that I would like to have, which is a close-up photograph of the object or some material sample from it, because if you have a close-up photograph or you actually get close to an object, you can tell if it’s a rock or a spacecraft. Any person can do that. The only way to deny that it might be something else is by not having enough evidence. If we are in a situation of uncertainty, and we see an object that behaves in ways that we do not understand; for example it displays non-gravitational acceleration without a cometary tail, and you don’t know how it’s maneuvering, and you don’t have an image of it; then you can say: “well, it’s a rock of a type that I’ve never seen before,” which is what the experts are saying. And so, the only way to figure it out is to actually get a high-resolution image, which in principle will immediately tell us what the object is. Or you can look for some additional signatures of technology. For example, artificial lights. If the object has artificial lights and is not just reflecting sunlight, then that would be a clear technological signature. If we see the object maneuvering in ways that cannot be explained, with accelerations far greater than we expect for any comet. An object that wants to stay within the solar system will come into the solar system and could stop, by braking. That would be a clear technological signature. There are lots of those. And in terms of materials, obviously we can tell the difference between stainless steel and rocky material, right? In September 2020, there was an object that was identified by the same telescope in Hawaii that discovered `Oumuamua, the 1st interstellar object. The observers saw a new object which they labeled 2020 SO, and realized that it’s being pushed by reflecting sunlight. Really strange. They collected the spectrum of this object and found that it’s made of stainless steel. And then they realized: oh, wait a minute, this object is actually a rocket booster, an upper stage of a surveyor lunar lander. They realized that NASA launched this object in 1966 and it is technological. And then, of course, they never wrote a paper about it. Because why would they discuss an object that happens to be technological that NASA launched? But think of what would happen if the same object would have been manufactured by another civilization. What would they do? It is not clear that they would follow on it and conclude that this is actually technological because they don’t know who launched it and it looks like it’s moving along a path that we’ve never launched an object into. So, they might continue to classify it as a dark comet. Q: How do you interpret objects such as `Oumuamua and 3I/ATLAS, and what features make them scientifically unusual or significant in your view? A: Both objects showed anomalies, but none of the anomalies was conclusive in flagging a technological origin. So, I defined a new Loeb Classification Scale in July 2025 after 3I/ATALS was discovered. This is a classification scale of interstellar objects where 0 implies a natural object and 10 implies a technological object of potential threat to humanity. alien technology. I gave both of 1I/`Oumuamua and 3I/ATLAS a rank of order 4 because they showed anomalies, but these anomalies were not conclusively technological. In the case of `Oumuamua, it was the fact that it had an extreme shape. As it was tumbling every 8 hours, the amount of sunlight reflected from the object changed by a factor of 10. And that meant that the object had an extreme shape, where one axis is at least 10 times longer than the other axis projected on the sky. In addition, the object was pushed away from the sun by some mysterious force without showing any cometary outgassing. So, I suggested that it may be pushed away from the Sun by reflecting sunlight. That was consistent with the decline of this non-gravitational acceleration, inversely with the square of the distance from the Sun. But that required that the object be extremely thin and flat. And nature doesn’t make such objects, so I suggested it may be technological. Just like 2020 SO, the previous object I had mentioned, which was discovered 3 years later. These were the main anomalies of `Oumuamua. There were some others, but these were the main ones. For 3I/ATLAS, there were other anomalies. It was much bigger than `Oumuamua, at least a factor of 10 or so, which means a factor of a 1,000 or more in mass. And that means that we should have seen, many more `Oumuamua-like objects for any object as big as 3I/ATLAS, which we did not. 3I/ATLAS also arrived within 5 degrees of the plane of the planets around the Sun. And the chance of that happening at random is 1 in 500. It also didn’t show a standard commentary tail, but had an anti-tail; namely a jet pointed towards the Sun rather than away from the Sun. And it had an abundance of deuterium that is 1000 times higher than the mean cosmic abundance. It had biological markers in the form of methane and other organic molecules. It had a system of 3 jets coming from its nucleus that are equally spaced on the sky by 120 degrees and unusual for pockets of ice on the surface of a rock. It also displayed nickel with very little iron. Usually, nickel and iron have a similar abundance in astrophysical objects, but not in industrial production of nickel alloys. 3I/ATLAS displayed very different anomalies than `Oumuamua; some of them were geometric, some of them had to do with composition. But again, one can say: “well, it’s an extremely rare and unusual object. So, we might have been lucky that it came this way.” I listed 22 anomalies in a recent summary essay on this object, posted here. Q: Is our search for extraterrestrial life necessarily limited to bio-signatures or techno-signatures, or should we remain open to the possibility that extraterrestrial life might take forms that do not fit our standard assumptions? A: Of course. The way I approach it is to search for things that are not familiar. I’m not trying to imagine that they use the radio communication approach that we developed a century ago. That’s what the SETI community has been focusing on for the past 65 years. And I think it’s misguided to keep searching for a very primitive mode of communication that we developed at the beginning of our technological evolution. When you keep looking and you’re not finding anything, that’s not a good practice to keep doing the same thing, expecting a different result. In my view, we should approach it differently. Looking for a package in our mailbox is very different than waiting for a phone call. And so that’s the approach I’m taking with the Galileo Project. And I also wrote papers about searching for artificial lights on the night side of exoplanets. When an exoplanet goes around the star, one hemisphere is illuminated by the starlight, and the opposite hemisphere is dark. And so, if you monitor the light reflected from the planet, you can tell at which phase it is along its orbit, just like the phases of the Moon. But if there is artificial light on the night side, or there is heat produced on the night side which is otherwise cold, you might be able to detect it as additional light that has nothing to do with the illumination by the star. So that’s a different techno signature. Another is to search for industrial pollution in the atmosphere of exoplanets, and I wrote the 1st paper that quantified that with my student and a post-doc a decade ago. There are various molecules that we produce industrially, and if another civilization might wish to purposely put a blanket of pollution in its atmosphere so that the planet — which is otherwise too cold — will get warmer. It’s a clear technological signature because these molecules are not produced by nature, the kind of CFCs is that we produce with our industries. Any there are more ways to search for technological. You can search for mega-structures around the habitable regions of stars. Unfortunately, the SETI community is too traditional. They keep doing what they were doing and recently started to follow the community of astrobiology. The focus of the mainstream is to search for the molecular fingerprints of life on exoplanets by seeking specific molecules in their atmospheres, like oxygen, methane, water, or carbon dioxide. However, even if we find those molecules, it will not be a conclusive fingerprint of life because the same molecules could be produced by geological processes that do not involve life. The astrobiology community is locked on investing more than ten billion dollars over the next 2 decades on developing the Habitable World Observatory. But nearly zero federal funding is allocated to the search for technological signatures, and I don’t think that’s wise. Even though microbes might be far more abundant, the signatures of technology could be easier to identify. And if we if we find tech signatures, then we would have not only evidence for life, but also for intelligence. Q: Which technological breakthroughs or new tools do you see as crucial for future progress in this field of study or interest? A: It depends on which signature one is looking for. In the context of interstellar objects, for example, trying to see if any of them might be technological. And by the way, I should say rocks that arrive into the solar system randomly from outer space, but technological probes may arrive preferentially to the inner part of the solar system for the same reason that bees are clustered around flowers. They might have a larger concentration around resources they are interested in. The habitable region might be of interest to them for some reason. And so the abundance of probes that we see are not representative of the average abundance in interstellar space, because we reside in the habitable zone of the Sun. This requires monitoring the sky for incoming objects. Right now, we have the Rubin Observatory in Chile that is monitoring the southern sky with a 3.2 gigapixel camera, and the hope is that it will discover dozens of interstellar objects in the coming decade. But we don’t have a survey telescope in the northern sky and there is a plan for the Argus array, which will do the same there. So having both survey telescopes to cover the entire sky would be essential. And then the question is: how do we get a high-resolution image of an object? For that, we need the much bigger telescope than currently available on Earth or in space. For example, we can build an optical interferometer on the Moon that is at least 100 meters in diameter. That could resolve the image of an object like 3I/ATLAS from the Moon without a flyby near the object. Finally, we need to design interceptors. These are space missions that could cross the path of incoming interstellar objects of interest, get much more data about them, and potentially also mitigate the risk if they happen to be heading towards Earth. This might become a high priority if we identify a technological object from outside the solar system. If we had a high-resolution image of an interstellar object, and we realize that it is technological, we should have a contingency plan for how to intercept it. Also, if we happen to notice a very interesting iceberg, it would make sense to land on it and bring materials back to Earth, because then we can check the materials for any building blocks of life as we know it. And that’s a completely different approach to astrobiology that is not recognized. I’m the only one advocating for that. Nobody is discussing it among astrobiologists. This approach is very different than building a huge telescope to look at the atmosphere of an exoplanet and figure out whether it has molecules that are indicative of life. Here we are examining material that came from another star far away. And the only reason we can do that is because there was this interstellar object that spent billions of years traveling through interstellar space from the parent star and arrived to our backyard. Ee should take advantage of that. I cannot understand how astrobiologists are not excited about this opportunity with interstellar objects as a new path to finding whether the material in planetary disks around other stars has the ingredients for life as we know it. Q: What you hope to recover from the ocean in the Galileo project or future similar projects and how would such a finding relate to the hypothesis of extraterrestrial life or possible technical signatures? A: In June 2023, I led an expedition to the Pacific Ocean aiming to recover materials from the 1st recognized interstellar meteor that exploded there in 2014 based on data from US government sensors. Ee went there and collected materials from the bottom of the ocean. There will be a Netflix documentary about it. I encourage all of you to check it out when it comes out, hopefully this year. At first, we analyze the chemical composition of the materials and found that about 10% of the molten droplets or spherules that we identified within the original material, has a chemical composition very different from solar system materials. There was an enhancement in some elements of like beryllium, lanthanum or uranium, by up to a factor of 1,000 relative to solar system materials. More recently, we engaged in additional studies of isotopes. I should also note that we recovered only molten droplets that are less than a millimeter in size, so we can’t tell the nature of the object. We cannot infer if this meteor is a Voyager-like probe or just a rock that came from another star. Obviously, most likely, it’s a rock, but to figure out that it’s natural — we have to get a sample of bigger fragments because the fragments that we retrieved were melted by the fireball of the explosion, when this object entered the earth’s atmosphere. Q: What concrete results have you achieved so far in your projects and is there any finding that has been particularly surprising or emotionally significant? A: By the way, I’m not driven by emotion. Significance for me is evidence. Although you might say that searching for a partner in our cosmic neighborhood is the most romantic search in science. But this is a blind date of interstellar proportions, meaning that we don’t know what will be on the other side. The only thing is I’m aiming high. When I went dating at a young age before I met my wife, I was trying to find someone who is more intelligent than I am. But what my fellow astrobiologists are doing is aim low. They say that microbes are far more abundant, so let’s search for them. It’s just like going on dates and saying that since mediocre partners are far more abundant, we should search for a mediocre partner. I don’t think that’s the right attitude. I want to find something that will give us inspiration, an encounter that would reveal new levels of science and technology, that could bring us to a better place. That’s the kind of partner I want to find. So even if mediocre partners are far more abundant, I would never marry one of those. We cannot imagine what may be out there because our experience is limited to this Earth, and to only one century of modern science and technology. Aliens may represent our future if there are a thousand years, a million years, a billion years more advanced than we are. We have no idea how they might look like. And so, our imagination is limited. I don’t care what script writers in Hollywood imagine. It’s probably very different. Actually, Steven Spielberg, when I met him one time, said: “Please tell me if you find anything. Let me be the first to know.” He also recognizes that his imagination is limited. All in all, you know, we should be open-minded and hope for something more advanced and collect data that would educate us about it. Q: If you made a groundbreaking discovery, how would you choose to communicate it? Would you do it through traditional scientific channels or faster and more public forums? Or would you just call Steven Spielberg? A: One thing is clear. I also would not waste any time going to Stockholm in your country. Why would I go to a Nobel cocktail party, dressed up, and waste my time in chatting with people, when I can actually learn more about our cosmic neighbors? That’s far more fascinating. So, I will actually follow Bob Dylan in just ignoring the phone call from the Nobel committee if I get one from Stockholm. But coming back to your previous question, I should say that we are currently within the Galileo Project at a very important phase where we are measuring distances to objects in the sky. We have three observatories that we constructed. Measuring distances allows us to infer the velocity and acceleration of objects that that appear as outliers relative to human made technologies. With respect to expeditions for materials from interstellar objects, we have identified another interstellar meteor from 2022. I would love to go and search for its materials off the coast of Peru. This expedition will cost about six million dollars and at the moment we are seeking potential funders. The funder could join us onboard the ship. Q: How is this type of research funded and which actors have an interest in the results? Do you see any patterns among interest parties? A: We are funded in part by foundations that are interested in the research. For example, most recently, the Templeton Foundation’s president visited me and said that he would like his Foundation to be involved with any discoveries we make. So, he provided a generous donation to the Galileo project, which I’m grateful for. We were also funded independently to construct an observatory on top of Sphere in Las Vegas which is the largest entertainment center in the world, about 100-meters in height, and we placed a Galileo Observatory on top of it. Timothy Chalamet, the main actor of a ping-pong player in a recent movie called Marty Supreme, filmed the promo for the movie on top of Sphere when it was lit up as a giant ping-pong ball. If you look at the promo images, you would see the Galileo Observatory next to him. The newspaper articles about the promo said that he was the first person to stand on top of Sphere, but it cannot be true because our observatories were put there half a year before he went there. This is an example for funding that we receive from individuals in addition to foundations that, because these individuals have interest in the research that we are doing. At the moment, we are not receiving any funding from federal agencies, which in a way gives us freedom to do the research with no strings attached. Q: How do security interests and military involvement affect the research, if at all? A: Frankly, I find any human-made objects boring. And that means that what the Pentagon and the intelligence agencies are interested in, which are human-made technologies that might be produced by adversarial nations, is completely uninteresting for me. I’m happy to give them all the data that relates to human-made objects. But I would hope that in return, I’ll receive some data from them that cannot be assigned to human-made technologies. Actually, tomorrow is a soft deadline for a request for the Pentagon to release 46 videos of Unidentified Anomalous Phenomena (UAP) based on a request letter submitted by Representative Anna Paulina Luna. I don’t know which fraction of these videos will be released but we might know more tomorrow, or maybe the deadline will be extended. I am hoping to meet Representative Luna and speak with her about it. But the idea is that if government has anomalous data that can be declassified, that would be of great interest to scientists like myself, and I’ll be happy to help government figure out the nature of these unusual objects. That includes videos of objects maneuvering in ways that we don’t understand, or it could even include materials from crash sites of such objects. You can understand why the government would be the first to notice UAP. This is because most astronomers use telescopes that are focused on a small part of the sky and are interested in very distant sources of light. They ignore anything close to Earth. So, astronomers will not find rare UAP, but the government that monitors the sky for national security purposes would be the first to notice them after monitoring the sky for many decades with the best equipment. The military and intelligence agencies also have a much larger budget than astronomers. So, they might be the first to notice unusual things, and they would keep the data classified because it was collected by classified sensors, and they don’t want adversarial nations to know about the capabilities of these sensors. And also, if they are unable to figure out what these objects are, they don’t want to show their vulnerability in terms of not being able to figure out things that they’re observing. For those reasons, it is obvious why such data would be classified. But my hope is that if government has data from a long time ago that is irrelevant to the battlefield today, or they have data that cannot be explained by human-made technologies for sure — they might just put it out this data a degraded form. I’ll be happy to look into it. Q: How do you assess the credibility of the testimonies and the information presented. For example, in the US Congressional hearings on UAP. A: Science is based on the collection of data by instruments, and you might ask why. The answer is simple. Look at the judicial system, which is attending to reports by humans. There are convicts who were put on death row, about to be executed. And then came evidence from DNA tests that indicated that they are innocent and they were exonerated. What does that tell you? It implies that people were testifying under oath, being absolutely sure that they are telling the truth. But these people were wrong. How is that possible? Well, if you are ever involved in a car accident, then when the police officers come along and ask the different parties involved in the car accident: “what happened?”, they get very different reports. People cannot be trusted. Why? Because they have a biased view of reality. They have wishful thinking. And they have an agenda sometimes. That was a lesson learned from history when Galileo looked through his telescope and saw moons orbiting Jupiter, and then was put in house arrest by the Vatican which had a different opinion. In 1992, the Vatican admitted that Galileo was right, but he was already 350 years dead. And what that tells you is that people have a lot of reasons for saying things. Obviously, the young people here know that from social media. If they use a dating app, they should not believe most of the profiles displayed there. Right? And so, the point is that people are not scientific instruments. When people tell you: “I’m absolutely convinced that something happened”, you might not believe them even if they are completely sincere about it, because someone told them or they thought they saw something that did not exist, or all kinds of circumstances might lead them to say something that is not real. Therefore, eyewitness testimonies from people who worked in government who say that they know about programs, are not sufficient for me as a scientist. They are intriguing in the sense that I believe those people. They are probably very sincere in what that’s saying, but the testimonies by themselves do not hold water, so to speak. I would like to see the actual evidence. I want to see the data. I want to see if there is material evidence. It’s very simple. And that’s a very elementary request. Obviously, it’s sufficient to see one thing. I’m not asking for dozens of different objects. I just want one. If you have one clear piece of evidence, that’s it. We’re done. If we want to convince ourselves that we are not alone, that there is someone else out there, just one piece of evidence beyond any reasonable doubt, collected by instruments or representing material evidence that we can examine in laboratory, would be sufficient. So just give me one thing. I don’t need 46 videos, dozens of reports. I just want one. Q: If a verified discovery of extraterrestrial life or technology were made, how do you think governments and authorities would act? Do you believe there are any contingency plans for this type of discovery? A: Some people claim that the government authorities already have evidence, and they have a plan or that are discussing how to release the data. That is called the process of disclosure, and they would do it gradually by first asking Steven Spielberg to release the movie Disclosure Day in June 2026 in order to prepare the public mentally. They might be worried that disclosure will disrupt the financial markets, that it will induce societal unrest. Governments have their authority because they promise their citizens that they can protect them. But in case there is a threat from alien technology that governments have no way of protecting their citizens against, there will be societal unrest. And all kinds of crazies will start going running down the street and doing all kinds of crazy stuff. And so that may be one reason for releasing such information gradually. However, the way I think of this is that if you were to go to the backyard of your home and you found a tennis ball that was thrown by a neighbor, and then at the dinner table you would insist not to release that information to your family members, then I don’t think it’s a good practice because the neighbor is still out there. You know about it because you found the tennis ball among the rocks in your backyard. So, you know that there is something out there. And that neighbor may knock on the front door one day or may affect the lives of your family members. It makes very little sense to hold this information away from humanity. We are all in the same boat. We should know whether we have neighbors in our cosmic street. For the same reason that the Vatican was not supposed to censor the information that Galileo Galilei revealed with his telescope, we should not censor or keep under wraps the information that alien tech might be visiting us. The fundamental question is whether the authorities actually have that information. If government does get access to such information or if through the Galileo Project I get access to it, the ultimate goal must be to share it with all humans. I see more benefit out of disclosure than negative repercussions, because we will recalibrate what we think about reality, and then we will start adapting to it. It’s like any other disruption. We developed advanced AI recently and AI is also very disruptive to society. Many of the people on this call may not have job opportunities that they were hoping to have because of AI. And what do you do about it? Do you just avoid the bad news to those young people who may not have a job of the type that they were dreaming about? For example, there are little future prospects for coders, people who write computer codes. In my generation, there were many people that invested their career in code writing, but we are obligated to tell aspiring coders about that job risk in the age of AI. Why? Because then they will adapt to the new reality and do something else. If you avoid the bad news, these people would make career mistakes that would harm them in the future. In my view, it is always good to know the reality that you live in. You must be sober to realize what the facts are and then decide how to adapt to them, how to cope with them. That’s the better approach. If you deny the reality by having magical thinking, your future will be worse. By the way, even rational people, business people or scientists, sometimes prefer to have magical thinking. Steve Jobs had pancreatic cancer but refused conventional medical treatment for it for nine months during which he utilized dietary changes, juice fasting and consultation with a psychic while the tumor was growing and spreading. He later expressed regret over this decision since it shortened his lifespan. Q: What does the scientific criticism of this research look like in general? And are there particular disciplines or groups that are more skeptical? And how do you respond to that criticism? A: Over the years, I wrote more than a thousand scientific papers. I started in cosmology, which is the study of the universe at large. And now I’m doing some work related to objects near Earth that could be comets or asteroids. What I can say is that the community of scholars working on cosmology is more like a community of chess players. They think abstractly and strategically, they appreciate original thoughts and because they don’t know the answer to many things, like the nature of dark matter and dark energy. They appreciate innovative thoughts that can be tested experimentally. They are not very dogmatic. However, astronomers who focus on studying rocks or icebergs in space make a community that resembles mud wrestlers more than chess players. The thing is that I don’t want to get dirty, so I don’t mud wrestle. Why do I say mud wrestling? Because they would basically bring you to the ground. Get you into the mud, and make sure that your voice is not heard just in order to preserve their prejudice that an object must be a rock of a type that they’ve never seen before and nothing else. I have many examples to report about, including by reviewers and editors of journals, but I will not waste your time on that because I prefer to focus on positive things. Some of these critics want to bring me to a negative mindset where I would focus on them because they have nothing better to do than to criticize. You might ask, why are terrorists sometimes more effective than governments? It is because in order to destroy something you don’t need to do a lot. You just need to put an explosive and destroy a building. But to create this building, you need to put a huge amount of work. Destroying is much easier than building. That’s why terrorist groups are effective, because they can destroy with very little effort. And therefore, they get a lot of attention. For the same reason, you can think about the construction of new concepts or ideas or scientific programs. It’s much easier to destroy those. How do you destroy them? First of all, you argue that there is no basis for this research project, that is completely unfounded, that in fact an interstellar meteor was actually a mistake made by the U.S. government. It’s not real, and maybe it actually happened somewhere else, and maybe the materials that were collected by the Galileo Project are just human-made materials, and maybe it was just a truck that passed near that side that gave the impression that there was a meteor there, but it was not really there. It was somewhere else. And you can just throw a lot of dust in the air and say that you don’t see anything. And that is done by people who don’t want any discussion on the possibility that an interstellar meteor might have been discovered. If this effort is not sufficiently effective, what they will do is take it to a second level where they would attack me personally and say bad things about me. You might say, if this is done by accomplished scientists, criticism is a fair game. But most of the people who write bad things and making negative YouTube videos with personal statements about me, are those who were not good enough to get an academic position. These are people who dropped out of academia. One of them calls himself a professor, even though he never held any professorship, not to speak about tenure track position or advanced research position. He dropped out of academia but calls himself a professor and then talks about me negatively. How dare he do that without practicing science? He is just a blogger on YouTube that gets attention by attacking me without doing anything productive. You just need to look at the resume of people who gain visibility in the public’s eye and ask: did they publish a single scientific paper over the past decade? Why should we trust them in telling us what science needs to be like? I am a practicing scientist. I published several new papers every month, and these people are telling me how to do science. It’s really ridiculous these days that people can get a lot of attention for pretending to represent science, even though they don’t have the credentials for being practicing scientists, and they throw mud at people who are practicing science like myself. I asked myself, how dare they do that? But that’s the reality of social media, a very unfortunate reality of misinformation. There are also people who created YouTube channels starting in November 2025 with content being spoken in my voice and in my image, AI-generated fake YouTube videos. Because of that, I decided three months ago to create my own YouTube channel just in order to fight those fake videos. These agents of misinformation are mudding the waters and people who watch them have a hard time deciding whether their content is authentic or misinformation. And it’s really an unfortunate part of the online culture that we have right now. Q: What’s your favorite depiction of extraterrestrial in pop culture? A: I don’t like science fiction. I like science and I enjoy fiction, but not the mix of the two because the storyline often violates the laws of physics and I feel uneasy about those violations. But an artist named Greg Wyatt, one the most accomplished sculptor in the US, delivered two bronze sculptures of Galileo Galilei and fifty-one watercolors that he created to my office at Harvard. But the biggest gift that he awarded me was the foundation for a new sculpture. He gave me plastelina, which is this material that you can use to make the shape of an intended sculpture that will eventually be cast in bronze. And I decided to call my new sculpture “The Alien”. I crafted a body of an alien by imagining what would an ideal body, better than the human body, look like. One thing I regret, for example, is that I don’t have a third eye because I cannot look backwards. It would have been great if we could see backwards as well, right? So, I put a 3rd eye for this alien and I put also wings so that the alien would be able to fly in a gaseous atmosphere. And I put a third leg which gives a more stable posture for the alien and I put some electronic or technological components in the alien body. Altogether, I created a model of an alien and Greg just sent me two days ago four photographs of this sculpture which is now made in red wax, and then eventually it will be cast in bronze. This is my first sculpture, a very different image of an alien than you find in science fiction movies. But that’s what my imagination produces. And once the bronze sculpture is done, I’ll be glad to show you how it looks. The images of the wax version are available on my recent post here. Q: How do you think pop culture representations influence our view of extraterrestrial life? Like, for example, the idea that they would be humanoid and they would be similar to us. A: I think pop culture affected a lot. It also affected testimonies of potential pilots that may have been retrieved along with materials from crash sites. But I would be really surprised if these imagined humanoid figures represent reality because if they arrived from a distant star, then the trip must have been very long, and biological bodies are not designed to survive such a long journey, while being exposed to energetic particles, cosmic rays. Just going to a low-gravity environment removes about 1.5% per month of the bone mass in our body and that means if we stay for several years on the Moon, our body would crumble, not to speak about the exposure to cosmic rays and micrometeorites without the protection of an atmosphere. A micrometeorite hit would pierce through our body like a bullet. Small micrometeorites burn up in the Earth’s atmosphere so we don’t think about the risk from them. The Earth’s atmosphere is like a womb, protecting us from a lot of the risks in outer space, such as cosmic rays and micrometeorites. All in all, the human body is not suitable for long distance travel, despite what you see in science fiction movies like “Project Hail Mary” — where a human survives a long trip to another star — making very little sense. I believe that sending robots with AI would make much more sense because they will not get bored during the journey, their material structure will be sustainable for long trips and they would not suffer in a low gravity environment. Therefore, if I imagine an alien visit my guess is that it involves a craft or probe being controlled by artificial intelligence, not by natural intelligence. That is why I’m a little bit skeptical about humanoids. Q: How do how do you interpret recurring descriptions of UFOs with strong lights on them? Could such lights serve a function if they were extraterrestrial crafts, or do they rather suggest natural phenomena that have been misinterpreted like ball lightning of charged clouds? A: One has to deal with each case on its merit, and most importantly, we need to know the distance of what we are seeing, and that would allow us to infer the speed and the acceleration. So, without distance information, it’s really difficult to tell because you can have something flying close to the camera that would look like a fast-moving object at a large distance. But if you have a second camera separated from the first one, then you will be able to tell that the object does not appear in both cameras or if it does appear, you can infer the distance. It’s really the quality of the data that matters. You can’t make general statements. So far, I haven’t seen conclusive evidence for alien technology. I would love to see the most intriguing cases that the US government or anyone else may have, and analyze that data. If there is a clear-cut case, it would be a learning experience. Most of the scientific community does not invest in this kind of research, and that is inappropriate given that the government talks about things it cannot identify and the public cares so much about it. So, our duty as scientists is to figure it out. At the very least, we will help the government figure out things that they cannot, and it will be important for national security. But of course, if we find something that is non-human made, then that would be a huge leap forward for humanity. Q: How do you view recurring reports of an anomalous phenomenon in the ocean? And is there anything you find particularly interesting or underestimated in these reports? If you know about them. A: We have more information about the surface of the moon than we have about the bottom of the oceans on Earth. It’s quite possible that there are surprising things down there, especially because there are reports on objects that go from the water to air or back in ways that are really anomalous. It’s possible the U.S. government has more data on that, and I would love to see it. It’s certainly a subject that is worth attending to. Q: In conclusion, do you have anything you’d like to tell the students in this class who may have a scientific interest for studying UAP? A: Well, my advice is very simple. Stay true to your childhood curiosity, and ignore people who pretend to be the adults in the room. Because as soon as there will be conclusive data, indicating perhaps that there are alien technological objects within the solar system, as soon as the data will be clear, everyone will start saying: “of course, we suspected that, we talked about it. There is nothing really new here. Look, I actually mentioned it before”, and it will become a common knowledge at that point. That’s what happened with the idea that the Earth moves around the Sun. By now, it’s impossible to deny it and so the Vatican is onboard. But it took many centuries for that to happen. And the best way to stay ignorant is by claiming that there is nothing to study, that in fact we should not invest any funds in the search, in the study of anomalies, because anomalies can be shoved under the rug of conventional thinking. And that’s what the people who pretend to be the adults in the room often say. They tell kids: “I know the answer to your question. There is no need to check it.” But the beauty of being a child or having a beginner’s mind — and by the way I’m 64 years old so biologically I’m definitely not a child but the way I think is still like a child — the benefit of being with a mindset of a child or a beginner is that you say: “Well, you are telling me that this round object is just a beach ball. Let me go and check, so the kid goes to the object and turns it around, checks it out. That’s what the kid does because that’s the process of learning while the adult says: “I don’t have to go and check it. I know what it is.” That’s the approach of someone who pretends to be the adult in the room, but my point is that adults with this mindset will never discover something that fundamentally shakes their worldview. Whereas if you maintain your childhood curiosity, you might be the one to deliver news to humanity. And so that’s a great privilege. It sounds like it’s really a dangerous thing to do to behave like a child, but in fact it’s a great privilege. Somehow, when people become adults, they deny themselves from having the privilege to behave that way. And when I speak to adults, I can see the child in them. Every adult, has some spark of childhood curiosity but they suppress it. They suppress it and that’s why they develop gray hair. That’s why they’re frustrated and not happy with their life. I bring them the news that they can be free of these chains. They don’t need to develop gray hair and a grudge as they get older. They can stay curious. Why is that so difficult? Q: Thank you very much for answering our questions, so passionately. So fascinating to listen to and we are very grateful for your time and generously answering all those questions. Looking forward to perhaps inviting you again in the future. A: I hope to have some exciting new evidence to show you within a year. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

(Image credit: ScienceDirect)The four astronauts on Artemis II were in space for 9 days and did not suffer any significant medical problems from the low gravity environment that they experienced. But for space journeys lasting years, it is necessary to produce an analog of Earth’s gravity in order to protect astronaut health. Without gravity, bones lose mineral density at a rate of about 1.5% per month and muscles atrophy rapidly. Bodily fluids move towards the head, potentially causing eye damage and brain swelling. There are two simple ways to produce artificial gravity. One is by accelerating astronauts on a rocket or any other propulsion system. The artificial linear acceleration would be indistinguishable from gravity for the passengers, for the same reason that gravity is not experienced in a free-falling elevator. The challenge with this method is to have sufficient fuel for a prolonged acceleration phase. Steady acceleration at 1-gee for a full year brings a payload to the speed of light. This means that the required energy for a year-long journey equals the rest-mass of the payload. Chemical rocket fuel only converts a billionth of its rest mass to pure energy. Nuclear fusion of deuterium-tritium fuel converts 0.37% of the fuel rest mass to energy. In order to accelerate at 1-gee for a year and reach the speed of light, a rocket must carry anti-matter fuel that would annihilate a mass of matter comparable to that of the payload. CERN produces about a billionth of a gram of antimatter per year. To accelerate a lightweight 140-kilogram human at 1-gee for a full year would require CERN to produce antimatter for 140 trillion years, a period ten thousand times longer than the current age of the Universe. The more practical method for generating artificial gravity is to spin a large structure so that the centripetal force would push passengers against the outer walls away from the rotation axis with a force that feels like gravity. This can be realized in a torus or a wheel-like structure or with two modules connected by a long tether and rotated around a common center. To create the Earth-like gravity of 1-gee, equal to 9.8 meters per second squared, without causing dizziness for human passengers from high rotation speeds, the radius of the rotating structure needs to be larger than the Artemis II Space Launch System. A system with a radius of 100 meters needs to rotate three times per minute in order to generate a centripetal acceleration of 1-gee. A system with a radius of 1-kilometer needs about one rotation per minute. The centripetal acceleration scales as the radius divided by the square of the rotation-period. The surface gravity on the Moon is 16.6% of the 1-gee on Earth. On Mars the value is 38% of gee. The health hazard for astronauts spending extended periods time on a permanent human base on the Moon needs more attention from NASA or space corporations like SpaceX or Blue Origins. If humans will need to stay on the Moon or Mars for extended periods of time, one could imagine creating “artificial gravity health centers” for them, equipped with huge centrifuges measuring a kilometer in radius and rotating once per minute. Local residents will visit these rotating giant structures periodically to get the “1-gee experience” and rejuvenate their bodies. This is the kind of infrastructure that nobody talks about. Other health risks on the Moon involve the exposure to energetic cosmic rays with 200 more radiation intensity than on Earth, enhancing the rates of cancer, central nervous system damage, and degenerative tissue effects. In addition, the lunar surface is covered with fine dust from asteroid impacts. Unlike dust on Earth, lunar dust was never eroded by wind or water, leaving it sharp like shattered glass. There is no place like home. *** Progress report on my first bronze sculpture: “The Alien” Five months ago, the accomplished artist Greg Wyatt gifted me two bronze sculptures of Galileo Galilei and 51 watercolors which transformed my Harvard office into a mini-museum. But Greg’s biggest gift was a chunk of plastelina for me to create an original sculpture, which I chose to name: “The Alien”. In crafting this sculpture, I imagined what an ideal alien body might include, supplementing the human body with a third eye, a third leg, wings, and technological devices. I shipped my creation to Greg three months ago. By now, my sculpture progressed to the next phase and was cast in red wax. Greg informed me of the wonderful news in an email and added that once the Alien sculpture is casted in bronze with a beautiful patina, he will make sure that it is mounted on an appropriate size cherrywood pedestal. I responded: “Dear Greg, This is amazing. The alien sculpture is becoming a reality. I will do my best to discover a real alien for comparison before the sculpture is cast in bronze. With deep gratitude. Avi” Below are three perspectives of the red wax phase of the sculpture. (Image credit: Greg Wyatt)ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

Splashdown of the Orion capsule of the Artemis II mission in the Pacific Ocean. (Image credit: NASA)The Artemis II spacecraft carried four humans to a distance record of 406,771 (~0.4 million) kilometers away from Earth. How significant is this accomplishment in a cosmic perspective? To gauge this feat, consider the cosmic ladder in distance jumps of roughly a factor of 10,000 per step. At a distance 10,000 bigger than the Artemis II record, lies the farthest planet in the Solar System, Neptune, of about 4.5 billion (4.5x10⁹) kilometers. Another factor of 10,000 brings us to the distance of the nearest star, Proxima Centauri, of about 40 trillion (4x10^{13}) kilometers. The diameter of the orbit of the Sun around the Milky-Way center is another factor of 10,000 up, of order 500 quadrillion (5x10^{17}) kilometers. The final step of 10,000 brings us to the largest cosmic scale over which the distribution of galaxies is clustered, of order 4.6 sextillion (4.6x10^{21}) kilometers. This is the scale of the so-called Baryonic Acoustic Oscillations (BAO), which serve as the largest yardstick for measuring the geometry of the Universe. The radius of the observable universe, the so-called cosmic particle horizon today, is approximately 100 times larger than the BAO scale, of order 440 sextillion (4.4x10^{23}) kilometers. We cannot observe what lies beyond that distance. This sets a limit to how far light had traveled since the Big Bang. But the limit on how far we can travel in the future is much smaller because of the accelerated expansion of the Universe. In order for a spacecraft to catch up with a distant galaxy, it must move faster than the recession speed of that galaxy. But given the accelerated expansion of the Universe, the task is even more daunting. The cosmic expansion is expected to be exponential in the future. This implies that irrespective of how fast we launch and how long we wait, a spacecraft would never catch up with galaxies beyond a certain distance from us. This is because distant galaxies will eventually be separated from us faster than light as a result of accelerated cosmic expansion. A spacecraft launched out of our galaxy at some speed could only reach a galaxy that is currently receding from us at a cosmic speed of less than half the spacecraft’s speed. This introduces the concept of a cosmic horizon for any launch speed, akin to prison walls for our travel ambitions. What would be the realistic expectations for future propulsion schemes that do better than chemical rockets? As I showed in a paper with my former postdoc, Manasvi Lingam, an ambitious space program could use light sails or electric sails to exceed the escape speed from the Milky Way. A spacecraft moving a hundred times faster than the speed of the five chemical rockets we sent so far to interstellar space could reach intergalactic space with a speed of 1000 kilometers per second, 0.3% of the speed of light. At that speed, it could catch up with galaxies that are currently within 5% of the BAO distance scale from us. But this spacecraft will never catch up with galaxies farther away, irrespective of how long we wait. The center of the nearest cluster of galaxies, the Virgo cluster, is about 15% of the BAO distance scale. Reaching beyond this distance requires spacecraft that move faster than a percent of the speed of light or 3,000 kilometers per second. Humanity’s most ambitious space travel initiative: Starshot — which I have the privilege of leading, aims to reach a speed that is an order of magnitude larger, above a tenth of the speed of light. This initiative envisions shining a powerful 100-gigawatt laser for a few minutes on a meter-size, gram-mass light sail. A Starshot probe could reach in the future galaxies that are out to the BAO distance scale. The cosmic horizon for intergalactic travel will include fewer destinations in our future because distant galaxies will keep accelerating away from us. We need to get our act together if we wish to reach them. As I had shown in a 2001 paper, once the Universe will age by a factor of ten — even a spacecraft moving at the speed of light will not be able to catch up with any galaxy beyond our own. All in all, we have a lot to aspire to in terms of our ambitions for space exploration. Long trips will likely be guided by robots with artificial intelligence (AI) rather than by humans with natural intelligence. The long travel time for communication signals, amounting to tens of thousands of years across the Milky-Way galaxy alone, will make real time communication futile. Launching interstellar mission with AI robots would feel like sending kids away from home to the world at large. It is unrealistic to expect frequent reports from them about their whereabouts. All we can hope for is that they will represent us well and spread our qualities of curiosity, integrity and intelligence to the Universe. Given that these AI robots will likely pass the Turing Test, they do not need to be made of flesh and blood in order to serve as effective ambassadors of humanity. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. Professional website: https://lweb.cfa.harvard.edu/~loeb/ Social media: https://avi-loeb.medium.com/ https://www.youtube.com/@ProfessorAviLoeb https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd https://x.com/ProfAviLoeb View the full article

A visualization of the Artemis I spacecraft reentering Earth’s atmosphere. Artemis II is about to splash down in the Pacific Ocean on April 10, 2026. (Image credit: NASA)Today, April 10, 2026, the Artemis II Orion spacecraft will bring back to Earth four humans who reached farther than any human did. The reentry of Orion through the Earth’s atmosphere will start at 8:07 PM ET with a velocity measuring 30 times the speed of sound. Like a giant piston, it will push air supersonically and generate a fireball capped by a blast wave with a temperature of thousands of degrees. The safety of the astronauts during this dramatic phase relies on the successful insolation provided by the heat shield surrounding the Orion capsule. Meteoroids often burn up and disintegrate into fragments during a similar journey, but that is because their structure and material strength was not designed to survive it. As they break up to pieces, the surface area increases and the power generated by friction of air keeps growing, generating further fragmentation in an explosive process. We all pray for a safer fireball ride during the Artemis II reentry. Below is a transcript of a new interview I had this morning in the company of former NASA Chief of Staff Gabriel (Gabe) Sherman, with the anchor Shannon Cake on Newsmax (accessible in video form here). Shannon’s questions are marked with SC, while my and Gabe’s answers are marked with AL and GS, respectively. (Image credit: Newsmax)SC: I want to bring in the director of the Institute for Theory and Computation at Harvard University this morning, Professor Avi Loeb, who has been walking us through this in recent days, and former NASA Chief of Staff Gabriel Sherman. Gentlemen: good morning to you. Full eyes on California just off the coast of San Diego today. This will be, Dr. Loeb, a tricky reentry maneuver. It’s set for this afternoon. So, the astronauts are set to wake about 11:30 AM ET this morning. They were up late last night into the early morning hours. They are going to wake up, start stowing their gear for this plan. It is called a lofted reentry, kind of like skipping off the atmosphere like a stone across the water. How tricky is it? Walk us through it, if you will. AL: Yes, the re-entry will start at around 8:07 PM ET. And the last time it was done was during the Artemis I mission where there was a skip. The capsule went down and then up again in order to go back down. And that created some problem for the heat shield. There were fragments from the heat shield that were lost. And that created a lot of concern. The hope is now to have much less of a skip, basically to go more smoothly down in a shorter path. The biggest amount of heat will be generated initially. As this capsule is moving at 25,000 miles per hour, a very high speed that creates a lot of friction on air because it’s about 30 times faster than the speed of sound. It creates a blast wave and a fireball surrounding the spacecraft, similar to the one around meteors, except the Orion capsule is protected by a heat shield. And we all pray that the heat shield will withstand the enormous amount of heat from the fireball. It involves a temperature of a few thousand degrees. SC: Fiery hot. Gabriel: how serious are the concerns leading into the reentry today on this heat shield? GS: I think anytime you’re doing this type of human exploration, there are concerns. But I think what we heard the associate administrator from NASA say is they’ve looked at this, they’ve walked through the tests, they’ve done the appropriate work, and they’ve changed the trajectory to ensure that we return our astronauts home safely. And so, this mission would not have moved forward had the people at NASA not been very confident that we were going to bring these heroes home safely. I look forward to that splashdown this evening. It’s going to be a historic day for us. We are all hoping and praying that everything goes according to plan today. SC: I want to play a quick clip of the NASA Administrator giving us an update, talking about that splashdown, gentlemen. To your point, Dr. Loeb. We’ll be watching for it, 8:07 PM ET off the coast of San Diego. “There’s no question that we’ll all be anxious. And, you know, but we’ll be with the families. We’ll be with them. We’ll all be together. You know, I have full confidence in the team. They do, too. You know, we’ve been with them the whole time. And so, you know, we’ve done the work. It’s impossible to say you don’t have irrational fears left, right? But I would tell you I don’t have any rational fears about what’s going to happen.” So, before we get to the splashdown, there’s going to be this six-minute blackout, no communication. They say, Gabriel, it’ll be a plasma envelope that kind of forms around Orion. Why is this a critical time? GS: I think it’s really interesting to think about just how quickly this process plays out, right? You go from releasing the service module to, you know, this atmospheric reentry and this plasma phase where you’re at 25,000 miles an hour. And then with just in minutes, you’re all the way down to 17 miles an hour and landing safely in the ocean. And so that blackout, that’ll be a nervous time for everybody that’s watching because we want to maintain communications. But it’s expected, right? All of this stuff is expected. This whole process is planned out. The NASA engineers, the flight control team, the astronauts, they are ready for these moments. And so the six-minute blackout, totally normal. Of course, we want to regain communication as quickly as we can. And on the other side of that, we’ll see the parachutes deploy and bring them home safely. A breathless six minutes, perhaps, for all of us here on Earth and certainly friends and families and loved ones and all of NASA. SC: Dr. Loeb, can you explain a little bit more deeply this plasma envelope that will shield Orion? What is it? How does it deploy? And what are we looking for? AL: Yes, the physics is really simple. What happens is that this object is moving through air at a very high speed, 30 times faster than the speed of sound. It creates hot gas around it. It shocks the gas. And that temperature, as we mentioned before, is several thousand degrees. And so, as a result of that all the atoms and molecules in air lose their electrons. They bump into each other and you create a cloud of free electrons around the spaceship. And those electrons block communication signals. That’s inevitable. Of course, we can hope for better heat shields in the future, both in terms of having better technologies, but also artificial intelligence, AI, can allow us to design better materials. I really hope that in the future missions, we will be much more secure in our assessments as to the effectiveness of the heat shield. SC: Yeah, and of course, the Artemis I showed cracking in that heat shield. So, all of these steps and stages, the trajectory change and everything that you two have discussed, attempting to avoid all of that this time around. You’re looking at, meanwhile, some of these images that was captured by the crew. In this debrief yesterday afternoon, the astronauts said that they are coming home with even more and better data than these images that they’re sharing here. What kind of data, Gabriel, are you looking at? What are you most curious about? GS: So, I think for me, it’s all about setting the stage for Artemis III, IV and V. Right. You want to test this Orion system out and ensure each one of the life support systems, propulsion systems, everything is working as it needs to to ensure that we can continue this adventure of lunar exploration because it is so critical at this point in history. And so, the most important information to me is the data that we gather on how all of these systems perform so that moving forward, we know we’re keeping our astronauts. safe as possible as we go even further and eventually move into a lunar landing. SC: Yesterday, Senator Cruz was talking about the astronauts. He basically said, you know, there’s a lot happening. He kind of walks it through. And they do make it look so easy, these astronauts, because they’ve backed up. They know each other’s roles and they can jump in at any time. Dr. Loeb, what are you looking for? What data are you most excited about unpacking? Basically, Senator Cruz was kind of walking us through what they do as they come back through and then they land and we grab them. It is very complicated and they back each other up. But what are you looking for this afternoon? In particular, in terms of duplication of roles, and also what are you most excited about unpacking when they finally do touchdown safely? AL: There is a lot of interesting science that can be recovered from this new data. They had a limited level of the data, only several tens of gigabytes that was transmitted per day. They carry with them much more. For example, if you look at the Moon, it started from a smooth surface of molten rock and now it’s scarred with all these impacts of asteroids and also interstellar objects — these are objects that came into the solar system from outside. We can learn a lot from these high-resolution images that the astronauts provide. They also saw six flashes of micrometeorites. These are tiny objects that collided with the moon. The moon doesn’t have an atmosphere. And so, these objects do not burn up. When they collide with Earth, they burn up in the atmosphere. But there on the Moon, they just hit the surface and you see a crater for each of them. The Moon is a museum of everything that impacted on it in the past 4.5 billion years. And I’m personally very interested to see if these are only rocks. Or maybe there are some technological artifacts, some objects that came from other civilizations that, you know, just by chance collided with the Moon. I calculated yesterday that an object like 3I/Atlas, which was the latest interstellar object, roughly the size of a city, two kilometers in diameter, has a 20% probability of colliding with the Moon over the Moon’s history. So, there are lots of things that can be found by looking into the items on this museum that we can find. As complex as the data that you gentlemen will get excited about and our scientists will unpack for years to come, I think you really simplified it well. SC: It is a museum of deep space. Professor Avi Loeb, director for the Institute of Theory and Computation at Harvard University and former NASA Chief of Staff Gabriel Sherman. We’re excited right along with you today. The entire country, the entire world indeed cheering alongside you. Thank you for your time. (Image credit: Newsmax)*** Let me close with tidbit: reality is complicated because when a system is composed of N units, there could be N² interactions among these units, making a full census of these interactions challenging even for our most advanced AI systems. ABOUT THE AUTHOR (Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, former director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics (2005–2026), and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024. 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