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By NASA
NASA named Stanford University of California winner of the Lunar Autonomy Challenge, a six-month competition for U.S. college and university student teams to virtually map and explore using a digital twin of NASA’s In-Situ Resource Utilization Pilot Excavator (IPEx).
The winning team successfully demonstrated the design and functionality of their autonomous agent, or software that performs specified actions without human intervention. Their agent autonomously navigated the IPEx digital twin in the virtual lunar environment, while accurately mapping the surface, correctly identifying obstacles, and effectively managing available power.
Lunar simulation developed by the winning team of the Lunar Autonomy Challenge’s first place team from Stanford University.Credit: Stanford University’s NAV Lab team Lunar simulation developed by the winning team of the Lunar Autonomy Challenge’s first place team from Stanford University.Credit: Stanford University’s NAV Lab team Team photo of NAV Lab Lunar Autonomy Challenge from Stanford UniversityCredit: Stanford University’s NAV Lab team The Lunar Autonomy Challenge has been a truly unique experience. The challenge provided the opportunity to develop and test methods in a highly realistic simulation environment."
Adam dai
Lunar Autonomy Challenge team lead, Stanford University
Dai added, “It pushed us to find solutions robust to the harsh conditions of the lunar surface. I learned so much through the challenge, both about new ideas and methods, as well as through deepening my understanding of core methods across the autonomy stack (perception, localization, mapping, planning). I also very much enjoyed working together with my team to brainstorm different approaches and strategies and solve tangible problems observed in the simulation.”
The challenge offered 31 teams a valuable opportunity to gain experience in software development, autonomy, and machine learning using cutting-edge NASA lunar technology. Participants also applied essential skills common to nearly every engineering discipline, including technical writing, collaborative teamwork, and project management.
The Lunar Autonomy Challenge supports NASA’s Lunar Surface Innovation Initiative (LSII), which is part of the Space Technology Mission Directorate. The LSII aims to accelerate technology development and pursue results that will provide essential infrastructure for lunar exploration by collaborating with industry, academia, and other government agencies.
The work displayed by all of these teams has been impressive, and the solutions they have developed are beneficial to advancing lunar and Mars surface technologies as we prepare for increasingly complex missions farther from home.”
Niki Werkheiser
Director of Technology Maturation and LSII lead, NASA Headquarters
“To succeed, we need input from everyone — every idea counts to propel our goals forward. It is very rewarding to see these students and software developers contributing their skills to future lunar and Mars missions,” Werkheiser added.
Through the Lunar Autonomy Challenge, NASA collaborated with the Johns Hopkins Applied Physics Laboratory, Caterpillar Inc., and Embodied AI. Each team contributed unique expertise and tools necessary to make the challenge a success.
The Applied Physics Laboratory managed the challenge for NASA. As a systems integrator for LSII, they provided expertise to streamline rigor and engineering discipline across efforts, ensuring the development of successful, efficient, and cost-effective missions — backed by the world’s largest cohort of lunar scientists.
Caterpillar Inc. is known for its construction and excavation equipment and operates a large fleet of autonomous haul trucks. They also have worked with NASA for more than 20 years on a variety of technologies, including autonomy, 3D printing, robotics, and simulators as they continue to collaborate with NASA on technologies that support NASA’s mission objectives and provide value to the mining and construction industries.
Embodied AI collaborated with Caterpillar to integrate the simulation into the open-source driving environment used for the challenge. For the Lunar Autonomy Challenge, the normally available digital assets of the CARLA simulation platform, such as urban layouts, buildings, and vehicles, were replaced by an IPEx “Digital Twin” and lunar environmental models.
“This collaboration is a great example of how the government, large companies, small businesses, and research institutions can thoughtfully leverage each other’s different, but complementary, strengths,” Werkheiser added. “By substantially modernizing existing tools, we can turn today’s novel technologies into tomorrow’s institutional capabilities for more efficient and effective space exploration, while also stimulating innovation and economic growth on Earth.”
FINALIST TEAMS
First Place
NAV Lab team
Stanford University, Stanford, California
Second Place
MAPLE (MIT Autonomous Pathfinding for Lunar Exploration) team
Massachusetts Institute of Technology, Cambridge, MA
Third Place
Moonlight team
Carnegie Mellon University, Pittsburgh, PA
OTHER COMPETING TEAMS
Lunar ExplorersArizona State UniversityTempe, ArizonaAIWVU West Virginia University Morgantown, West VirginiaStellar Sparks California Polytechnic Institute Pomona Pomona, California LunatiX Johns Hopkins University Whiting School of EngineeringBaltimore CARLA CSU California State University, Stanislaus Turlock, CaliforniaRose-Hulman Rose-Hulman Institute of Technology Terre Haute, IndianaLunar PathfindersAmerican Public University SystemCharles Town, West Virginia Lunar Autonomy Challenge digital simulation of lunar surface activity using a digital twin of NASA’s ISRU Pilot ExcavatorJohns Hopkins Applied Physics Laboratory Keep Exploring Discover More Topics From NASA
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Game Changing Development projects aim to advance space technologies, focusing on advancing capabilities for going to and living in space.
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By NASA
4 min read
May’s Night Sky Notes: How Do We Find Exoplanets?
Astronomers have been trying to discover evidence that worlds exist around stars other than our Sun since the 19th century. By the mid-1990s, technology finally caught up with the desire for discovery and led to the first discovery of a planet orbiting another sun-like star, Pegasi 51b. Why did it take so long to discover these distant worlds, and what techniques do astronomers use to find them?
The Transit Method
A planet passing in front of its parent star creates a drop in the star’s apparent brightness, called a transit. Exoplanet Watch participants can look for transits in data from ground-based telescopes, helping scientists refine measurements of the length of a planet’s orbit around its star. Credit: NASA’s Ames Research Center One of the most famous exoplanet detection methods is the transit method, used by Kepler and other observatories. When a planet crosses in front of its host star, the light from the star dips slightly in brightness. Scientists can confirm a planet orbits its host star by repeatedly detecting these incredibly tiny dips in brightness using sensitive instruments. If you can imagine trying to detect the dip in light from a massive searchlight when an ant crosses in front of it, at a distance of tens of miles away, you can begin to see how difficult it can be to spot a planet from light-years away! Another drawback to the transit method is that the distant solar system must be at a favorable angle to our point of view here on Earth – if the distant system’s angle is just slightly askew, there will be no transits. Even in our solar system, a transit is very rare. For example, there were two transits of Venus visible across our Sun from Earth in this century. But the next time Venus transits the Sun as seen from Earth will be in the year 2117 – more than a century from the 2012 transit, even though Venus will have completed nearly 150 orbits around the Sun by then!
The Wobble Method
As a planet orbits a star, the star wobbles. This causes a change in the appearance of the star’s spectrum called Doppler shift. Because the change in wavelength is directly related to relative speed, astronomers can use Doppler shift to calculate exactly how fast an object is moving toward or away from us. Astronomers can also track the Doppler shift of a star over time to estimate the mass of the planet orbiting it. NASA, ESA, CSA, Leah Hustak (STScI) Spotting the Doppler shift of a star’s spectra was used to find Pegasi 51b, the first planet detected around a Sun-like star. This technique is called the radial velocity or “wobble” method. Astronomers split up the visible light emitted by a star into a rainbow. These spectra, and gaps between the normally smooth bands of light, help determine the elements that make up the star. However, if there is a planet orbiting the star, it causes the star to wobble ever so slightly back and forth. This will, in turn, cause the lines within the spectra to shift ever so slightly towards the blue and red ends of the spectrum as the star wobbles slightly away and towards us. This is caused by the blue and red shifts of the star’s light. By carefully measuring the amount of shift in the star’s spectra, astronomers can determine the size of the object pulling on the host star and if the companion is indeed a planet. By tracking the variation in this periodic shift of the spectra, they can also determine the time it takes the planet to orbit its parent star.
Direct Imaging
Finally, exoplanets can be revealed by directly imaging them, such as this image of four planets found orbiting the star HR 8799! Space telescopes use instruments called coronagraphs to block the bright light from the host star and capture the dim light from planets. The Hubble Space Telescope has captured images of giant planets orbiting a few nearby systems, and the James Webb Space Telescope has only improved on these observations by uncovering more details, such as the colors and spectra of exoplanet atmospheres, temperatures, detecting potential exomoons, and even scanning atmospheres for potential biosignatures!
NASA’s James Webb Space Telescope has provided the clearest look in the infrared yet at the iconic multi-planet system HR 8799. The closest planet to the star, HR 8799 e, orbits 1.5 billion miles from its star, which in our solar system would be located between the orbit of Saturn and Neptune. The furthest, HR 8799 b, orbits around 6.3 billion miles from the star, more than twice Neptune’s orbital distance. Colors are applied to filters from Webb’s NIRCam (Near-Infrared Camera), revealing their intrinsic differences. A star symbol marks the location of the host star HR 8799, whose light has been blocked by the coronagraph. In this image, the color blue is assigned to 4.1 micron light, green to 4.3 micron light, and red to the 4.6 micron light. NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI) You can find more information and activities on NASA’s Exoplanets page, such as the Eyes on Exoplanets browser-based program, The Exoplaneteers, and some of the latest exoplanet news. Lastly, you can find more resources in our News & Resources section, including a clever demo on how astronomers use the wobble method to detect planets!
The future of exoplanet discovery is only just beginning, promising rich rewards in humanity’s understanding of our place in the Universe, where we are from, and if there is life elsewhere in our cosmos.
Originally posted by Dave Prosper: July 2015
Last Updated by Kat Troche: April 2025
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By NASA
4 min read
Entrepreneurs Challenge Winner PRISM is Using AI to Enable Insights from Geospatial Data
PRISM’s platform uses AI segmentation to identify and highlight residential structures in a neighborhood. NASA sponsored Entrepreneurs Challenge events in 2020, 2021, and 2023 to invite small business start-ups to showcase innovative ideas and technologies with the potential to advance the agency’s science goals. To potentially leverage external funding sources for the development of innovative technologies of interest to NASA, SMD involved the venture capital community in Entrepreneurs Challenge events. Challenge winners were awarded prize money, and in 2023 the total Entrepreneurs Challenge prize value was $1M. Numerous challenge winners have subsequently refined their products and/or received funding from NASA and external sources (e.g., other government agencies or the venture capital community) to further develop their technologies.
One 2023 Entrepreneurs Challenge winner, PRISM Intelligence (formerly known as Pegasus Intelligence and Space), is using artificial intelligence (AI) and other advances in computer vision to create a new platform that could provide geospatial insights to a broad community.
Every day, vast amounts of remote sensing data are collected through satellites, drones, and aerial imagery, but for most businesses and individuals, accessing and extracting meaningful insights from this data is nearly impossible.
The company’s product—Personal Real-time Insight from Spatial Maps, a.k.a. PRISM—is transforming geospatial data into an easy-to-navigate, queryable world. By leveraging 3D computer vision, geospatial analytics, and AI-driven insights, PRISM creates photorealistic, up-to-date digital environments that anyone can interact with. Users can simply log in and ask natural-language questions to instantly retrieve insights—no advanced Geographic Information System (GIS) expertise is required.
For example, a pool cleaner looking for business could use PRISM to search for all residential pools in a five-mile radius. A gardener could identify overgrown trees in a community. City officials could search for potholes in their jurisdiction to prioritize repairs, enhance public safety, and mitigate liability risks. This broad level of accessibility brings geospatial intelligence out of the hands of a few and into everyday decision making.
The core of PRISM’s platform uses radiance fields to convert raw 2D imagery into high-fidelity, dynamic 3D visualizations. These models are then enhanced with AI-powered segmentation, which autonomously identifies and labels objects in the environment—such as roads, vehicles, buildings, and natural features—allowing for seamless search and analysis. The integration of machine learning enables PRISM to refine its reconstructions continuously, improving precision with each dataset. This advanced processing ensures that the platform remains scalable, efficient, and adaptable to various data sources, making it possible to produce large-scale, real-time digital twins of the physical world.
The PRISM platform’s interface showcasing a 3D digital twin of California State Polytechnic University, Pomona, with AI-powered search and insights. “It’s great being able to push the state of the art in this relatively new domain of radiance fields, evolving it from research to applications that can impact common tasks. From large sets of images, PRISM creates detailed 3D captures that embed more information than the source pictures.” — Maximum Wilder-Smith, Chief Technology Officer, PRISM Intelligence
Currently the PRISM platform uses proprietary data gathered from aerial imagery over selected areas. PRISM then generates high-resolution digital twins of cities in select regions. The team is aiming to eventually expand the platform to use NASA Earth science data and commercial data, which will enable high-resolution data capture over larger areas, significantly increasing efficiency, coverage, and update frequency. PRISM aims to use the detailed multiband imagery that NASA provides and the high-frequency data that commercial companies provide to make geospatial intelligence more accessible by providing fast, reliable, and up-to-date insights that can be used across multiple industries.
What sets PRISM apart is its focus on usability. While traditional GIS platforms require specialized training to use, PRISM eliminates these barriers by allowing users to interact with geospatial data through a frictionless, conversational interface.
The impact of this technology could extend across multiple industries. Professionals in the insurance and appraisal industries have informed the company how the ability to generate precise, 3D assessments of properties could streamline risk evaluations, reduce costs, and improve accuracy—replacing outdated or manual site visits. Similarly, local governments have indicated they could potentially use PRISM to better manage infrastructure, track zoning compliance, and allocate resources based on real-time, high-resolution urban insights. Additionally, scientists could use the consistent updates and layers of three-dimensional data that PRISM can provide to better understand changes to ecosystems and vegetation.
As PRISM moves forward, the team’s focus remains on scaling its capabilities and expanding its applications. Currently, the team is working to enhance the technical performance of the platform while also adding data sources to enable coverage of more regions. Future iterations will further improve automation of data processing, increasing the speed and efficiency of real-time 3D reconstructions. The team’s goal is to expand access to geospatial insights, ensuring that anyone—from city planners to business owners—can make informed decisions using the best possible data.
PRISM Intelligence founders Zachary Gaines, Hugo Delgado, and Maximum Wilder-Smith in their California State Polytechnic University, Pomona lab, where the company was first formed. Share
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Explore This Section Webb News Latest News Latest Images Blog (offsite) Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Deployment Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 5 Min Read NASA’s Webb Images Young, Giant Exoplanets, Detects Carbon Dioxide
NASA’s James Webb Space Telescope has provided the clearest look in the infrared yet at the iconic multi-planet system HR 8799. Full image below. Credits:
NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI) NASA’s James Webb Space Telescope has captured direct images of multiple gas giant planets within an iconic planetary system. HR 8799, a young system 130 light-years away, has long been a key target for planet formation studies.
The observations indicate that the well-studied planets of HR 8799 are rich in carbon dioxide gas. This provides strong evidence that the system’s four giant planets formed much like Jupiter and Saturn, by slowly building solid cores that attract gas from within a protoplanetary disk, a process known as core accretion.
The results also confirm that Webb can infer the chemistry of exoplanet atmospheres through imaging. This technique complements Webb’s powerful spectroscopic instruments, which can resolve the atmospheric composition.
“By spotting these strong carbon dioxide features, we have shown there is a sizable fraction of heavier elements, like carbon, oxygen, and iron, in these planets’ atmospheres,” said William Balmer, of Johns Hopkins University in Baltimore. “Given what we know about the star they orbit, that likely indicates they formed via core accretion, which is an exciting conclusion for planets that we can directly see.”
Balmer is the lead author of the study announcing the results published today in The Astrophysical Journal. Balmer and their team’s analysis also includes Webb’s observation of a system 97 light-years away called 51 Eridani.
Image A: HR 8799 (NIRCam Image)
NASA’s James Webb Space Telescope has provided the clearest look in the infrared yet at the iconic multi-planet system HR 8799. The closest planet to the star, HR 8799 e, orbits 1.5 billion miles from its star, which in our solar system would be located between the orbit of Saturn and Neptune. The furthest, HR 8799 b, orbits around 6.3 billion miles from the star, more than twice Neptune’s orbital distance. Colors are applied to filters from Webb’s NIRCam (Near-Infrared Camera), revealing their intrinsic differences. A star symbol marks the location of the host star HR 8799, whose light has been blocked by the coronagraph. In this image, the color blue is assigned to 4.1 micron light, green to 4.3 micron light, and red to the 4.6 micron light. NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI) Image B: 51 Eridani (NIRCam Image)
Webb’s NIRCam (Near-Infrared Camera) captured this image of 51 Eridani b (also referred to as 51 Eri b), a cool, young exoplanet that orbits 890 million miles from its star, similar to Saturn’s orbit in our solar system. The 51 Eridani system is 97 light-years from Earth. This image includes filters representing 4.1-micron light as red. The background red in this image is not light from other planets, but a result of light subtraction during image processing. NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI) HR 8799 is a young system about 30 million years old, a fraction of our solar system’s 4.6 billion years. Still hot from their tumultuous formation, the planets within HR 8799 emit large amounts of infrared light that give scientists valuable data on how they formed.
Giant planets can take shape in two ways: by slowly building solid cores with heavier elements that attract gas, just like the giants in our solar system, or when particles of gas rapidly coalesce into massive objects from a young star’s cooling disk, which is made mostly of the same kind of material as the star. The first process is called core accretion, and the second is called disk instability. Knowing which formation model is more common can give scientists clues to distinguish between the types of planets they find in other systems.
“Our hope with this kind of research is to understand our own solar system, life, and ourselves in the comparison to other exoplanetary systems, so we can contextualize our existence,” Balmer said. “We want to take pictures of other solar systems and see how they’re similar or different when compared to ours. From there, we can try to get a sense of how weird our solar system really is—or how normal.”
Image C: Young Gas Giant HR 8799 e (NIRCam Spectrum)
This graph shows a spectrum of one of the planets in the HR 8799 system, HR 8799 e. Spectral fingerprints of carbon dioxide and carbon monoxide appear in data collected by Webb’s NIRCam (Near-Infrared Camera). NASA, ESA, CSA, STScI, J. Olmsted (STScI) Of the nearly 6,000 exoplanets discovered, few have been directly imaged, as even giant planets are many thousands of times fainter than their stars. The images of HR 8799 and 51 Eridani were made possible by Webb’s NIRCam (Near-Infrared Camera) coronagraph, which blocks light from bright stars to reveal otherwise hidden worlds.
This technology allowed the team to look for infrared light emitted by the planets in wavelengths that are absorbed by specific gases. The team found that the four HR 8799 planets contain more heavy elements than previously thought.
The team is paving the way for more detailed observations to determine whether objects they see orbiting other stars are truly giant planets or objects such as brown dwarfs, which form like stars but don’t accumulate enough mass to ignite nuclear fusion.
“We have other lines of evidence that hint at these four HR 8799 planets forming using this bottom-up approach” said Laurent Pueyo, an astronomer at the Space Telescope Science Institute in Baltimore, who co-led the work. “How common is this for planets we can directly image? We don’t know yet, but we’re proposing more Webb observations to answer that question.”
“We knew Webb could measure colors of the outer planets in directly imaged systems,” added Rémi Soummer, director of STScI’s Russell B. Makidon Optics Lab and former lead for Webb coronagraph operations. “We have been waiting for 10 years to confirm that our finely tuned operations of the telescope would also allow us to access the inner planets. Now the results are in and we can do interesting science with it.”
The NIRCam observations of HR 8799 and 51 Eridani were conducted as part of Guaranteed Time Observations programs 1194 and 1412 respectively.
The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.
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Johns Hopkins University, Baltimore, Md.
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By NASA
This artist’s illustration represents the results from a new study that examines the effects of X-ray and other high-energy radiation unleashed on potential exoplanets from Wolf 359, a nearby red dwarf star. Researchers used Chandra and XMM-Newton to study the impact of steady X-ray and energetic ultraviolet radiation from Wolf 359 on the atmospheres of planets that might be orbiting the star. They found that only a planet with greenhouse gases like carbon dioxide in its atmosphere and at a relatively large distance away from Wolf 359 would have a chance to support life as we know it.X-ray: NASA/CXC/SAO/S.Wolk, et al.; Illustration: NASA/CXC/SAO/M.Weiss; Image processing: NASA/CXC/SAO/N. Wolk Planets around other stars need to be prepared for extreme weather conditions, according to a new study from NASA’s Chandra X-ray Observatory and ESA’s (European Space Agency’s) XMM-Newton that examined the effects of X-rays on potential planets around the most common type of stars.
Astronomers found that only a planet with greenhouse gases in its atmosphere like Earth and at a relatively large distance away from the star they studied would have a chance to support life as we know it around a nearby star.
Wolf 359 is a red dwarf with a mass about a tenth that of the Sun. Red dwarf stars are the most common stars in the universe and live for billions of years, providing ample time for life to develop. At a distance of only 7.8 light-years away, Wolf 359 is also one of the closest stars to the solar system.
“Wolf 359 can help us unlock the secrets around stars and habitability,” said Scott Wolk of the Center for Astrophysics | Harvard & Smithsonian (CfA), who led the study. “It’s so close and it belongs to such an important class of stars – it’s a great combination.”
Because red dwarfs are the most prevalent types of stars, astronomers have looked hard to find exoplanets around them. Astronomers have found some evidence for two planets in orbit around Wolf 359 using optical telescopes, but those conclusions have been challenged by other scientists.
“While we don’t have proof of planets around Wolf 359 yet, it seems very possible that it hosts multiple planets,” Wolk added. “This makes it an excellent test bed to look at what planets would experience around this kind of star.”
Wolk and his colleagues used Chandra and XMM to study the amounts of steady X-rays and extreme ultraviolet (UV) radiation – the most energetic type of UV radiation – that Wolf 359 would unleash on the possible planets around it.
They found that Wolf 359 is producing enough damaging radiation that only a planet with greenhouse gases like carbon dioxide in its atmosphere – and located at a relatively large distance from the star – would likely be able to sustain life.
“Just being far enough away from the star’s harmful radiation wouldn’t be enough to make it habitable,” said co-author Vinay Kashyap, also of CfA. “A planet around Wolf 359 would also need to be blanketed in greenhouse gases like Earth is.”
To study the effects of energetic radiation on the habitability of the planet candidates, the team considered the star’s habitable zone – the region around a star where liquid water could exist on a planet’s surface.
The outer limit of the habitable zone for Wolf 359 is about 15% of the distance between Earth and the Sun, because the red dwarf is much less bright than the Sun. Neither of the planet candidates for this system is located in Wolf 359’s habitable zone, with one too close to the star and the other too far out.
“If the inner planet is there, the X-ray and extreme UV radiation it is subjected to would destroy the atmosphere of this planet in only about a million years,” said co-author Ignazio Pillitteri of CfA and the National Institute for Astrophysics in Palermo, Italy.
The team also considered the effects of radiation on as-yet undetected planets within the habitable zone. They concluded that a planet like the Earth in the middle of the habitable zone should be able to sustain an atmosphere for almost two billion years, while one near the outer edge could last indefinitely, helped by the warming effects of greenhouse gases.
Another big danger for planets orbiting stars like Wolf 359 is from X-ray flares, or occasional bright bursts of X-rays, on top of the steady, everyday output from the star. Combining observations made with Chandra and XMM-Newton resulted in the discovery of 18 X-ray flares from Wolf 359 over 3.5 days.
Extrapolating from these observed flares, the team expects that much more powerful and damaging flares would occur over longer periods of time. The combined effects of the steady X-ray and UV radiation and the flares mean that any planet located in the habitable zone is unlikely to have a significant atmosphere long enough for multicellular life, as we know it on Earth, to form and survive. The exception is the habitable zone’s outer edge if the planet has a significant greenhouse effect.
These results were presented at the 245th meeting of the American Astronomical Society in National Harbor, Maryland, and are being prepared for publication in a journal. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
Read more from NASA’s Chandra X-ray Observatory.
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