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By NASA
Scientists are following neon signs in a search for clues to one planetary system’s future and the past of another – our own solar system. Following up on a peculiar reading by NASA’s previous infrared flagship observatory, the now-retired Spitzer Space Telescope, the agency’s James Webb Space Telescope detected distinct traces of the element neon in the dusty disk surrounding the young Sun-like star SZ Chamaelontis (SZ Cha).
Image: SZ Chamaeleontis Protoplanetary Disk (Artist Concept )
In this artist concept, the young star SZ Chamaeleontis (SZ Cha) is surrounded by a disk of dust and gas with the potential to form a planetary system. Once our solar system looked something like this, before planets, moons, and asteroids formed. The raw ingredients, including those for life on Earth, were present in the Sun’s protoplanetary disk. SZ Cha emits radiation in multiple wavelengths which are evaporating the disk. Planets are in a race against time to form before the disk of material is evaporated completely. NASA’s James Webb Space Telescope observed typical conditions in the disk – it was being bombarded primarily by X-rays. However, when NASA’s Spitzer Space Telescope observed the disk in 2008, it saw a different scene, dominated by extreme ultraviolet (EUV) light, indicated by the presence of a specific type of neon in the disk. These differences are significant because planets would have more time to form from a disk dominated by EUV. Astronomers are investigating the cause of the difference between Webb and Spitzer’s readings, and think it may be due to the presence (or not) of a strong wind that, when active, absorbs EUV, leaving X-rays to hit the disk.NASA, ESA, CSA, Ralf Crawford (STScI) Differences in the neon readings between Spitzer and Webb point to a never-before-observed change in high-energy radiation that reaches the disk, which eventually causes it to evaporate, limiting the time planets have to form.
“How did we get here? It really goes back to that big question, and SZ Cha is the same type of young star, a T-Tauri star, as our Sun was 4.5 billion years ago at the dawn of the solar system,” said astronomer Catherine Espaillat of Boston University, in Massachusetts, who led both the 2008 Spitzer observations and the newly published Webb results. “The raw materials for Earth, and eventually life, were present in the disk of material that surrounded the Sun after it formed, and so studying these other young systems is as close as we can get to going back in time to see how our own story began.”
Scientists use neon as an indicator of how much, and what type, of radiation is hitting and eroding the disk around a star. When Spitzer observed SZ Cha in 2008, it saw an outlier, with neon readings unlike any other young T-Tauri disk. The difference was the detection of neon III, which is typically scarce in protoplanetary disks that are being pummeled by high-energy X-rays. This meant that the high-energy radiation in the SZ Cha disk was coming from ultraviolet (UV) light instead of X-rays. Besides being the lone oddball result in a sample of 50-60 young stellar disks, the UV vs. X-ray difference is significant for the lifetime of the disk and its potential planets.
Image: Neon Gas In Protoplanetary Disk
Contrasting data from NASA’s James Webb and Spitzer space telescopes show change in the disk surrounding the star SZ Chamaeleontis (SZ Cha) in just 15 years. In 2008, Spitzer’s detection of significant neon III made SZ Cha an outlier among similar young protoplanetary disks. However, when Webb followed up on SZ Cha in 2023, the ratio of neon II to III was within typical levels. All of this is significant because protoplanetary disks are the stuff of future planetary systems – and those potential planets are in a race against time. Astronomers use neon as an indicator of the dominant radiation hitting the disk and causing it to evaporate. When extreme ultraviolet light is dominant, there is more neon III. That is the unusual circumstance that Spitzer observed in 2008. Typically, a disk is dominated by X-ray radiation, which evaporates the disk more quickly, leaving planets less time to form. Researchers think the dramatic differences in neon detections are the result of a wind that, when present, absorbs ultraviolet light and leaves X-rays to pummel the disk. They will continue using Webb to find other examples of variability in disk conditions, working toward a better understanding of how planetary systems develop around Sun-like stars.NASA, ESA, CSA, Ralf Crawford (STScI) “Planets are essentially in a race against time to form up in the disk before it evaporates,” explained Thanawuth Thanathibodee of Boston University, another astronomer on the research team. “In computer models of developing systems, extreme ultraviolet radiation allows for 1 million more years of planet formation than if the evaporation is predominately caused by X-rays.”
So, SZ Cha was already quite the puzzle when Espaillat’s team returned to study it with Webb, only to find a new surprise: The unusual neon III signature had all but disappeared, indicating the typical dominance of X-ray radiation.
The research team thinks that the differences in neon signatures in the SZ Cha system are the result of a variable wind that, when present, absorbs UV light and leaves X-rays to pummel the disk. Winds are common in a system with a newly formed, energetic star, the team says, but it is possible to catch the system during a quiet, wind-free period, which is what Spitzer happened to do.
“Both the Spitzer and Webb data are excellent, so we knew this had to be something new we were observing in the SZ Cha system – a significant change in conditions in just 15 years,” added co-author Ardjan Sturm of Leiden University, Leiden, Netherlands.
Espaillat’s team is already planning more observations of SZ Cha with Webb, as well as other telescopes, to get to the bottom of its mysteries. “It will be important to study SZ Cha, and other young systems, in multiple wavelengths of light, like X-ray and visible light, to discover the true nature of this variability we’ve found,” said co-author Caeley Pittman of Boston University. “It’s possible that brief, quiet periods dominated by extreme UV radiation are common in many young planetary systems, but we just have not been able to catch them.”
“Once again, the universe is showing us that none of its methods are as simple as we might like to make them. We need to rethink, re-observe, and gather more information. We’ll be following the neon signs,” said Espaillat.
This research has been accepted for publication in Astrophysical Journal Letters.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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.
Media Contacts
Laura Betz – laura.e.betz@nasa.gov, Rob Gutro– rob.gutro@nasa.gov
NASA’s Goddard Space Flight Center, , Greenbelt, Md.
Leah Ramsay lramsay@stsci.edu , Christine Pulliam cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Downloads
Download full resolution images for this article from the Space Telescope Science Institute.
Research results have been accepted for publication in Astropyisical Journal Letters.
Related Information
How do Planets Form? https://exoplanets.nasa.gov/faq/43/how-do-planets-form/
Planetary Systems – https://universe.nasa.gov/stars/planetary-systems/
Webb Mission – https://science.nasa.gov/mission/webb/
Webb News – https://science.nasa.gov/mission/webb/latestnews/
Webb Images – https://science.nasa.gov/mission/webb/multimedia/images/
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James Webb Space Telescope
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
Planets
Our solar system can be divided into three regions: the inner solar system, the outer solar system, and the Kuiper…
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Overview Stars are giant balls of hot gas – mostly hydrogen, with some helium and small amounts of other elements.…
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Last Updated Nov 15, 2023 Editor Steve Sabia Contact Related Terms
Exoplanets Goddard Space Flight Center James Webb Space Telescope (JWST) Planets View the full article
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By NASA
Scientists using NASA’s James Webb Space Telescope just made a breakthrough discovery in revealing how planets are made. By observing water vapor in protoplanetary disks, Webb confirmed a physical process involving the drifting of ice-coated solids from the outer regions of the disk into the rocky-planet zone.
Theories have long proposed that icy pebbles forming in the cold, outer regions of protoplanetary disks — the same area where comets originate in our solar system — should be the fundamental seeds of planet formation. The main requirement of these theories is that pebbles should drift inward toward the star due to friction in the gaseous disk, delivering both solids and water to planets.
A fundamental prediction of this theory is that as icy pebbles enter into the warmer region within the “snowline” — where ice transitions to vapor — they should release large amounts of cold water vapor. This is exactly what Webb observed.
“Webb finally revealed the connection between water vapor in the inner disk and the drift of icy pebbles from the outer disk,” said principal investigator Andrea Banzatti of Texas State University, San Marcos, Texas. “This finding opens up exciting prospects for studying rocky planet formation with Webb!”
“In the past, we had this very static picture of planet formation, almost like there were these isolated zones that planets formed out of,” explained team member Colette Salyk of Vassar College in Poughkeepsie, New York. “Now we actually have evidence that these zones can interact with each other. It’s also something that is proposed to have happened in our solar system.”
Image: Planet-forming Disks
Artist’s Concept: This artist’s concept compares two types of typical, planet-forming disks around newborn, Sun-like stars. On the left is a compact disk, and on the right is an extended disk with gaps. Scientists using Webb recently studied four protoplanetary disks—two compact and two extended. The researchers designed their observations to test whether compact planet-forming disks have more water in their inner regions than extended planet-forming disks with gaps. This would happen if ice-covered pebbles in the compact disks drift more efficiently into the close-in regions nearer to the star and deliver large amounts of solids and water to the just-forming, rocky, inner planets. Current research proposes that large planets may cause rings of increased pressure, where pebbles tend to collect. As the pebbles drift, any time they encounter an increase in pressure, they tend to collect there. These pressure traps don’t necessarily shut down pebble drift, but they do impede it. This is what appears to be happening in the large disks with rings and gaps. This also could have been a role of Jupiter in our solar system — inhibiting pebbles and water delivery to our small, inner, and relatively water-poor rocky planets. NASA, ESA, CSA, Joseph Olmsted (STScI) Harnessing the Power of Webb
The researchers used Webb’s MIRI (the Mid-Infrared Instrument) to study four disks — two compact and two extended — around Sun-like stars. All four of these stars are estimated to be between 2 and 3 million years old, just newborns in cosmic time.
The two compact disks are expected to experience efficient pebble drift, delivering pebbles to well within a distance equivalent to Neptune’s orbit. In contrast, the extended disks are expected to have their pebbles retained in multiple rings as far out as six times the orbit of Neptune.
The Webb observations were designed to determine whether compact disks have a higher water abundance in their inner, rocky planet region, as expected if pebble drift is more efficient and is delivering lots of solid mass and water to inner planets. The team chose to use MIRI’s MRS (the Medium-Resolution Spectrometer) because it is sensitive to water vapor in disks.
The results confirmed expectations by revealing excess cool water in the compact disks, compared with the large disks.
Image: Water Abundance
Emission Spectrum – Water Abundance: This graphic compares the spectral data for warm and cool water in the GK Tau disk, which is a compact disk without rings, and extended CI Tau disk, which has at least three rings on different orbits. The science team employed the unprecedented resolving power of MIRI’s MRS (the Medium-Resolution Spectrometer) to separate the spectra into individual lines that probe water at different temperatures. These spectra, seen in the top graph, clearly reveal excess cool water in the compact GK Tau disk, compared with the large CI Tau disk. The bottom graph shows the excess cool water data in the compact GK Tau disk minus the cool water data in the extended CI Tau disk. The actual data, in purple, are overlaid on a model spectrum of cool water. Note how closely they align. NASA, ESA, CSA, Leah Hustak (STScI) As the pebbles drift, any time they encounter a pressure bump — an increase in pressure — they tend to collect there. These pressure traps don’t necessarily shut down pebble drift, but they do impede it. This is what appears to be happening in the large disks with rings and gaps.
Current research proposes that large planets may cause rings of increased pressure, where pebbles tend to collect. This also could have been a role of Jupiter in our solar system — inhibiting pebbles and water delivery to our small, inner, and relatively water-poor rocky planets.
Solving the Riddle
When the data first came in, the results were puzzling to the research team. “For two months, we were stuck on these preliminary results that were telling us that the compact disks had colder water, and the large disks had hotter water overall,” remembered Banzatti. “This made no sense, because we had selected a sample of stars with very similar temperatures.”
Only when Banzatti overlaid the data from the compact disks onto the data from the large disks did the answer clearly emerge: the compact disks have extra cool water just inside the snowline, at about ten times closer than the orbit of Neptune.
“Now we finally see unambiguously that it is the colder water that has an excess,” said Banzatti. “This is unprecedented and entirely due to Webb’s higher resolving power!”
Image: Icy Pebble Drift
This graphic is an interpretation of data from Webb’s MIRI, the Mid-Infrared Instrument, which is sensitive to water vapor in disks. It shows the difference between pebble drift and water content in a compact disk versus an extended disk with rings and gaps. In the compact disk on the left, as the ice-covered pebbles drift inward toward the warmer region closer to the star, they are unimpeded. As they cross the snow line, their ice turns to vapor and provides a large amount of water to enrich the just-forming, rocky, inner planets. On the right is an extended disk with rings and gaps. As the ice-covered pebbles begin their journey inward, many become stopped by the gaps and trapped in the rings. Fewer icy pebbles are able to make it across the snow line to deliver water to the inner region of the disk.NASA, ESA, CSA, Joseph Olmsted (STScI) The team’s results appear in the Nov. 8 edition of the Astrophysical Journal Letters.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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.
Media Contacts
Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Hannah Braun – hbraun@stsci.edu , Christine Pulliam – cpulliam@stsci.edi
Space Telescope Science Institute, Baltimore, Md.
Downloads
Download full resolution images for this article from the Space Telescope Science Institute.
Research results in the Nov. 8 edition of the Astrophysical Journal Letters.
Related Information
More about protoplanetary disks on NASA’s Universe website.
More Webb News – https://science.nasa.gov/mission/webb/latestnews/
More Webb Images – https://science.nasa.gov/mission/webb/multimedia/images/
Webb Mission Page – https://science.nasa.gov/mission/webb/
En Español
Ciencia de la NASA
NASA en español
Space Place para niños
Keep Exploring Related Topics
James Webb Space Telescope
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
Planets
Our solar system can be divided into three regions: the inner solar system, the outer solar system, and the Kuiper…
Exoplanets
Overview Most of the exoplanets discovered so far are in a relatively small region of our galaxy, the Milky Way.…
Universe
Explore the universe: Learn about the history of the cosmos, what it’s made of, and so much more.
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Last Updated Nov 08, 2023 Editor Steve Sabia Contact Related Terms
Goddard Space Flight Center James Webb Space Telescope (JWST) The Universe View the full article
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By European Space Agency
Governments and international disaster response teams have long relied on satellites to assess the impacts of disasters such as earthquakes and hurricanes. Now ESA has partnered with ICEYE, a Finnish microsatellite manufacturer, to improve early warning systems for floods and wildfires and extend their geographical coverage globally.
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By USH
The US Navy's engagement with UFO encounters is not a recent phenomenon. UFO sightings by the Navy can be traced back to the 1950s and 1960s. However, during that period, these sightings were shrouded in secrecy. Crew members were explicitly instructed to remain silent about the incidents, and when pressed, they were often provided with vague or nonsensical explanations regarding the nature of these mysterious objects.
Even with the latest official announcements of supposed UFO/USO encounters such as the USS Nimitz UFO Incident (2004) USS Theodore Roosevelt UFO Incident (2014-2015) USS Kidd UFO Incident (2019) USS Russell UFO Incident (2019) USS Omaha UFO Incident (2021) You can imagine that the US Navy has experienced many more UFO / USO encounters over the years but these events are kept secret.
Here are five UFO / USO incidents in which the US Navy has been involved during the 60's, 70's and 80's.
1. Azores Islands, Early fall 1965, USS Albany GC10 -Late at night, lights out, watch shift. Technician and air traffic controllers observed 3 unidentified objects on radar following the fleet at a distance of about 40-50 miles for over an hour. -Three jets deployed to investigate. The pilots flying at speeds of around 1350 nots, but failed to make visual contact with the unknown objects. The technician, however, could spot the bogies on the height-finding radar, SP530. -As the jets attempted to approach the UFOs, the objects moved away rapidly, maintaining their triangular formation.-Then, within seven radar sweeps, the UFOs had completely disappeared from the radar, while the jets remained visible.
2. Azores Islands, May 23, 1968, USS Monrovia APA-31-Witness was on board the USS Monrovia APA-31 and observed a large submerged object on the starboard side of the ship, just behind the stern. -This USO had an elongated oval shape and emitted a luminescent orange glow. It appeared to have a translucent quality. -The USO seemed to mimic several changes in the ship's compass, radar, and radio equipment to malfunction, rendering them inoperable.-As suddenly as it had appeared, the USO vanished. -The sighting lasted for about 90 minutes and was witnessed by around 1,100 members of the ship's crew, including a contingent of US Marines.
3. Mediterranean Sea, Summer 1974, USS Forrestal CV-59 -Signalman on duty during a regular night-watch spots an unusual reflection appearing as an underwater light, approximately 8 miles away and reports the sighting to the control tower. -Despite sonar failing to confirm the contact, the visual sighting was strong enough to bring the captain, executive officer, flight boss, and several intelligence officers to the deck. Over the next 20 minutes, they watch the object moving at high speed across the ship's bow. -The object zigzagged from 60 to over 100 miles per hour until it halted directly in the ship's path at one point within 4 miles of the Forrestal, before disappearing into the depths of the sea. -In the aftermath, the witness was ordered by the executive officer to remain silent.
4. Bermuda Triangle, June 15, 1977, USS Glover AGFF-1 -Early morning of June 15, 1977 witness's watch duty above the bridge interrupted by a bright red-orange circular object that dropped from the sky and neared the ship and almost simultaneously, another watch also spotted the object. -Within moments, two more similar objects appeared, compelling them to report 3 unidentified contacts to the bridge and the Combat Information Center (CIC). -Suddenly, the ship lost all power, including radar and sonar, and came to a standstill in the water while the 3 objects conducted astonishing maneuvers across the sky before forming a triangle directly above the ship. -The 3 objects then converged to form a single bright orange light circle about 200 yards directly above the ship. Then vanish and the ship regains full power, and all systems reboot. -Later that night, ship encounters a surface contact that moved at an estimated speed of 70 mph and dove underwater without any slowdown, eventually, it plunged into depths of the Atlantic, disappearing both from the sonar and radar screens. -The following morning, the crew was assembled and ordered to forget everything they had witnessed and told they had seen 'an experimental Russian helicopter.'
5. Caribbean Sea, Summer 1980 or 1981, USS W.S. Sims FF-1059 -An urgent dispatch was relayed to the USS W.S. Sims to head to Puerto Rico where there were reports of a Russian submarine exhibiting suspicious maneuvers in the area. -Onboard were divers, scientists and other experts, all brought together to investigate the unusual underwater activity. -The crew spent several intense weeks working to determine what exactly they were dealing with.-Witness heard "whispers" from the divers who were part of the investigation. They referred to the incident as another "Shag Harbor." -The final outcome of the mission remained elusive and the crew were told they had been studying a natural phenomenon of undetermined origin. -The phenomenon had the uncanny ability to elude detection at will, only to reappear again, this pattern continued for about six weeks.
The Shag Harbor UFO incident was the reported impact of an unknown large object into waters near Shag Harbor, Nova Scotia, a fishing village on the Atlantic coast, on 4 October 1967.
At least eleven people saw a low-flying lit object head towards the harbor. Multiple witnesses reported hearing a whistling sound "like a bomb," then a "whoosh," and finally a loud bang.
Two days after the incident had been observed, a detachment of navy divers from Fleet Diving Unit Atlantic was assembled and for the next three days, they combed the seafloor of the Gulf of Maine off Shag Harbor looking for an object.
The final report said no trace of an object was found but it is suggested that they kept this UFO incident secret.
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By European Space Agency
Fuelled largely by climate change, our planet is being subjected to environmental changes that are having an unprecedented global impact on humans, animals and plants. Shockingly, in certain locations these changes are occurring at a rate never before witnessed.
To keep pace with the challenges we face, ESA is embarking on a new Earth observation science strategy – and has reached out to the scientific community at this early stage in the process to help guide the Agency’s scientific agenda for the coming years.
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