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NASA’s Webb, Hubble Combine to Create Most Colorful View of Universe
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Explore Hubble Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Posters Hubble on the NASA App Glossary More 35th Anniversary Online Activities 2 min read
Hubble Comes Face-to-Face with Spiral’s Arms
This Hubble Space Telescope image showcases the spiral galaxy NGC 3596. ESA/Hubble & NASA, D. Thilker The spiral galaxy NGC 3596 is on display in this NASA/ESA Hubble Space Telescope image that incorporates six different wavelengths of light. NGC 3596 is situated 90 million light-years from Earth in the constellation Leo, the Lion. British astronomer Sir William Herschel first documented the galaxy in 1784.
NGC 3596 appears almost perfectly face-on when viewed from Earth, showcasing the galaxy’s neatly wound spiral arms. These bright arms hold concentrations of stars, gas, and dust that mark the area where star formation is most active, illustrated by the brilliant pink star-forming regions and young blue stars tracing NGC 3596’s arms.
What causes these spiral arms to form? It’s a surprisingly difficult question to answer, partly because spiral galaxies are so diverse. Some have clear spiral arms, while others have patchy, feathery arms. Some have prominent bars across their centers, while others have compact, circular nuclei. Some have close neighbors, while others are isolated.
Early ideas of how spiral arms formed stumped astronomers with the ‘winding problem’. If a galaxy’s spiral arms are coherent structures, its arms would wind tighter and tighter as the galaxy spins, until the arms are no longer visible. Now, researchers believe that spiral arms represent a pattern of high-density and low-density areas rather than a physical structure. As stars, gas, and dust orbit within a galaxy’s disk, they pass in and out of the spiral arms. Much like cars moving through a traffic jam, these materials slow down and bunch up as they enter a spiral arm, before emerging and continuing their journey through the galaxy.
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Last Updated May 09, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
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Explore Hubble Science Hubble Space Telescope NASA’s Hubble Pinpoints… Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Posters Hubble on the NASA App Glossary More 35th Anniversary Online Activities 7 Min Read NASA’s Hubble Pinpoints Roaming Massive Black Hole
This six-panel illustration of a tidal disruption event around a supermassive black hole shows the collision with a star followed by an explosion detected in X-ray as well as Hubble Space Telescope visible-light observations. Credits:
Artwork: NASA, ESA, STScI, Ralf Crawford (STScI) Like a scene out of a sci-fi movie, astronomers using NASA telescopes have found “Space Jaws.”
Lurking 600 million light-years away, within the inky black depths between stars, there is an invisible monster gulping down any wayward star that plummets toward it. The sneaky black hole betrayed its presence in a newly identified tidal disruption event (TDE) where a hapless star was ripped apart and swallowed in a spectacular burst of radiation. These disruption events are powerful probes of black hole physics, revealing the conditions necessary for launching jets and winds when a black hole is in the midst of consuming a star, and are seen as bright objects by telescopes.
The new TDE, called AT2024tvd, allowed astronomers to pinpoint a wandering supermassive black hole using NASA’s Hubble Space Telescope, with similar supporting observations from NASA’s Chandra X-Ray Observatory and the NRAO Very Large Array telescope that also showed that the black hole is offset from the center of the galaxy.
The paper will be published in an upcoming issue of The Astrophysical Journal Letters.
This six-panel illustration of a tidal disruption event around a supermassive black hole shows the following: 1) A supermassive black hole is adrift inside a galaxy, its presence only detectable by gravitational lensing; 2) A wayward star gets swept up in the black hole’s intense gravitational pull; 3) The star is stretched or “spaghettified” by gravitational tidal effects; 4) The star’s remnants form a disk around the black hole; 5) There is a period of black hole accretion, pouring out radiation across the electromagnetic spectrum, from X-rays to radio wavelengths; and 6) The host galaxy, seen from afar, contains a bright flash of energy that is offset from the galaxy’s nucleus, where an even more massive black hole dwells. Artwork: NASA, ESA, STScI, Ralf Crawford (STScI) Surprisingly, this one million-solar-mass black hole doesn’t reside exactly in the center of the host galaxy, where supermassive black holes are typically found, and actively gobble up surrounding material. Out of approximately 100 TDE events recorded by optical sky surveys so far, this is the first time an offset TDE has been identified. The rest are associated with the central black holes of galaxies.
In fact, at the center of the host galaxy there is a different supermassive black hole weighing 100 million times the mass of the Sun. Hubble’s optical precision shows the TDE was only 2,600 light-years from the more massive black hole at the galaxy’s center. That’s just one-tenth the distance between our Sun and the Milky Way’s central supermassive black hole.
This bigger black hole spews out energy as it accretes infalling gas, and it is categorized as an active galactic nucleus. Strangely, the two supermassive black holes co-exist in the same galaxy, but are not gravitationally bound to each other as a binary pair. The smaller black hole may eventually spiral into the galaxy’s center to merge with the bigger black hole. But for now, it is too far separated to be gravitationally bound.
A TDE happens when an infalling star is stretched or “spaghettified” by a black hole’s immense gravitational tidal forces. The shredded stellar remnants are pulled into a circular orbit around the black hole. This generates shocks and outflows with high temperatures that can be seen in ultraviolet and visible light.
“AT2024tvd is the first offset TDE captured by optical sky surveys, and it opens up the entire possibility of uncovering this elusive population of wandering black holes with future sky surveys,” said lead study author Yuhan Yao of the University of California at Berkeley. “Right now, theorists haven’t given much attention to offset TDEs. “I think this discovery will motivate scientists to look for more examples of this type of event.”
This is a Hubble Space Telescope image of distant galaxy that is host to the telltale signature of a roaming supermassive black hole. Science: NASA, ESA, STScI, Yuhan Yao (UC Berkeley); Image Processing: Joseph DePasquale (STScI) A Flash in the Night
The star-snacking black hole gave itself away when several ground-based sky survey telescopes observed a flare as bright as a supernova. But unlike a supernova, astronomers know that this came from a black hole snacking on a star because the flare was very hot, and showed broad emission lines of hydrogen, helium, carbon, nitrogen, and silicon. The Zwicky Transient Facility at Caltech’s Palomar Observatory, with its 1.2-meter telescope that surveys the entire northern sky every two days, first observed the event.
“Tidal disruption events hold great promise for illuminating the presence of massive black holes that we would otherwise not be able to detect,” said Ryan Chornock, associate adjunct professor at UC Berkeley and a member of the ZTF team. “Theorists have predicted that a population of massive black holes located away from the centers of galaxies must exist, but now we can use TDEs to find them.”
The flare was seemingly offset from the center of a bright massive galaxy as cataloged by Pan-STARRS (Panoramic Survey Telescope and Rapid Response System), the Sloan Digital Sky Survey, and the DESI Legacy Imaging Survey. To better determine that it was not at the galactic center, Yao’s team used NASA’s Chandra X-ray Observatory to confirm that X-rays from the flare site were also offset.
It took the resolving power of Hubble to settle any uncertainties. Hubble’s sensitivity to ultraviolet light also allows it to pinpoint the location of the TDE, which is much bluer than the rest of the galaxy.
This is a combined Hubble Space Telescope/Chandra X-Ray Observatory image of a distant galaxy that is host to the telltale signature of a roaming supermassive black hole. Both telescopes caught a tidal disruption event (TDE) caused by the black hole eating a star. Science: NASA, ESA, STScI, Yuhan Yao (UC Berkeley); Image Processing: Joseph DePasquale (STScI) Origin Unknown
The black hole responsible for the TDE is prowling inside the bulge of the massive galaxy. The black hole only becomes apparent every few tens of thousands of years when it “burps” from capturing a star, and then it goes quiet again until its next meal comes along.
How did the black hole get off-center? Previous theoretical studies have shown that black holes can be ejected out of the centers of galaxies because of three-body interactions, where the lowest-mass member gets kicked out. This may be the case here, given the stealthy black hole’s close proximity to the central black hole. “If the black hole went through a triple interaction with two other black holes in the galaxy’s core, it can still remain bound to the galaxy, orbiting around the central region,“ said Yao.
An alternative explanation is that the black hole is the surviving remnant of a smaller galaxy that merged with the host galaxy more than 1 billion years ago. If that is the case, the black hole might eventually spiral in to merge with the central active black hole sometime in the very far future. So at present, astronomers don’t know if it’s coming or going.
Erica Hammerstein, another UC Berkeley postdoctoral researcher, scrutinized the Hubble images as part of the study, but did not find any evidence of a past galaxy merger. But she explained, “There is already good evidence that galaxy mergers enhance TDE rates, but the presence of a second black hole in AT2024tvd’s host galaxy means that at some point in this galaxy’s past, a merger must have happened.”
Specialized for different kinds of light, observatories like Hubble and Chandra work together to pinpoint and better understand fleeting events like these. Future telescopes that will also be optimized for capturing transient events like this one include the National Science Foundation’s Vera C. Rubin Observatory and NASA’s upcoming Nancy Grace Roman Space Telescope. They will provide more opportunities for follow-up Hubble observations to zero in on a transient’s exact location.
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The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
ZTF is a public-private partnership, with equal support from the ZTF Partnership and from the U.S. National Science Foundation.
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Six panel illustration of Black Hole TDE AT2024tvd
This is a six-panel illustration of a tidal disruption event around a supermassive back hole.
Black Hole TDE AT2024tvdu00a0
This is a Hubble Space Telescope image of a distant galaxy that is host to the telltale signature of a roaming supermassive black hole.
Black Hole TDE AT2024tvd (Hubble + Chandra)
This is a combined Hubble Space Telescope/Chandra X-Ray Observatory image of a distant galaxy that is host to the telltale signature of a roaming supermassive black hole.
Black Hole TDE AT2024tvd Compass Image
This is a combined Hubble Space Telescope/Chandra X-Ray Observatory image of a distant galaxy that is host to the telltale signature of a roaming supermassive black hole.
Black Hole Tidal Disruption Event
This is a video animation of a tidal disruption event (TDE), an intense flash of radiation caused by the supermassive black hole eating a star. The video begins by zooming into a galaxy located 600 million light-years away.
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Last Updated May 08, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center
Contact Media Claire Andreoli
NASA’s Goddard Space Flight Center
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claire.andreoli@nasa.gov
Ray Villard
Space Telescope Science Institute
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Explore This Section Webb News Latest News Latest Images Webb’s Blog 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 New Visualization From NASA’s Webb Telescope Explores Cosmic Cliffs
The landscape of “mountains” and “valleys” known as the Cosmic Cliffs is actually a portion of the nebula Gum 31, which contains a young star cluster called NGC 3324. Both Gum 31 and NGC 3324 are part of a vast star-forming region known as the Carina Nebula Complex. Credits:
NASA, ESA, CSA, STScI. In July 2022, NASA’s James Webb Space Telescope made its public debut with a series of breathtaking images. Among them was an ethereal landscape nicknamed the Cosmic Cliffs. This glittering realm of star birth is the subject of a new 3D visualization derived from the Webb data. The visualization, created by NASA’s Universe of Learning and titled “Exploring the Cosmic Cliffs in 3D,” breathes new life into an iconic Webb image.
It is being presented today at a special event hosted by the International Planetarium Society to commemorate the 100th anniversary of the first public planetarium in Munich, Germany.
The landscape of “mountains” and “valleys” known as the Cosmic Cliffs is actually a portion of the nebula Gum 31, which contains a young star cluster called NGC 3324. Both Gum 31 and NGC 3324 are part of a vast star-forming region known as the Carina Nebula Complex.
Ultraviolet light and stellar winds from the stars of NGC 3324 have carved a cavernous area within Gum 31. A portion of this giant bubble is seen above the Cosmic Cliffs. (The star cluster itself is outside this field of view.)
The Cliffs display a misty appearance, with “steam” that seems to rise from the celestial mountains. In actuality, the wisps are hot, ionized gas and dust streaming away from the nebula under an onslaught of relentless ultraviolet radiation.
Eagle-eyed viewers may also spot particularly bright, yellow streaks and arcs that represent outflows from young, still-forming stars embedded within the Cosmic Cliffs. The latter part of the visualization sequence swoops past a prominent protostellar jet in the upper right of the image.
Video: Exploring the Cosmic Cliffs in 3D
In July 2022, NASA’s James Webb Space Telescope made history, revealing a breathtaking view of a region now nicknamed the Cosmic Cliffs. This glittering landscape, captured in incredible detail, is part of the nebula Gum 31 — a small piece of the vast Carina Nebula Complex — where stars are born amid clouds of gas and dust.
This visualization brings Webb’s iconic image to life — helping us imagine the true, three-dimensional structure of the universe… and our place within it.
Produced for NASA by the Space Telescope Science Institute (STScI) with partners at Caltech/IPAC, and developed by the AstroViz Project of NASA’s Universe of Learning, this visualization is part of a longer, narrated video that provides broad audiences, including youth, families, and lifelong learners, with a direct connection to the science and scientists of NASA’s Astrophysics missions. That video enables viewers to explore fundamental questions in science, experience how science is done, and discover the universe for themselves.
“Bringing this amazing Webb image to life helps the public to comprehend the three-dimensional structure inherent in the 2D image, and to develop a better mental model of the universe,” said STScI’s Frank Summers, principal visualization scientist and leader of the AstroViz Project.
More visualizations and connections between the science of nebulas and learners can be explored through other products produced by NASA’s Universe of Learning including a Carina Nebula Complex resource page and ViewSpace, a video exhibit that is currently running at almost 200 museums and planetariums across the United States. Visitors can go beyond video to explore the images produced by space telescopes with interactive tools now available for museums and planetariums.
NASA’s Universe of Learning materials are based upon work supported by NASA under award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Center for Astrophysics | Harvard & Smithsonian, and NASA’s Jet Propulsion Laboratory.
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 CSA (Canadian Space Agency).
NASA’s Universe of Learning is part of the NASA Science Activation program, from the Science Mission Directorate at NASA Headquarters. The Science Activation program connects NASA science experts, real content and experiences, and community leaders in a way that activates minds and promotes deeper understanding of our world and beyond. Using its direct connection to the science and the experts behind the science, NASA’s Universe of Learning provides resources and experiences that enable youth, families, and lifelong learners to explore fundamental questions in science, experience how science is done, and discover the universe for themselves.
To learn more about Webb, visit:
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Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Space Telescope Science Institute, Baltimore, Md.
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Explore more: Carina Nebula Complex from NASA’s Universe of Learning
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Last Updated May 07, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
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This NASA/ESA Hubble Space Telescope image features a peculiar spiral galaxy called Arp 184 or NGC 1961.ESA/Hubble & NASA, J. Dalcanton, R. J. Foley (UC Santa Cruz), C. Kilpatrick A beautiful but skewed spiral galaxy dazzles in this NASA/ESA Hubble Space Telescope image. The galaxy, called Arp 184 or NGC 1961, sits about 190 million light-years away from Earth in the constellation Camelopardalis (The Giraffe).
The name Arp 184 comes from the Atlas of Peculiar Galaxies compiled by astronomer Halton Arp in 1966. It holds 338 galaxies that are oddly shaped and tend to be neither entirely elliptical nor entirely spiral-shaped. Many of the galaxies are in the process of interacting with other galaxies, while others are dwarf galaxies without well-defined structures. Arp 184 earned its spot in the catalog thanks to its single broad, star-speckled spiral arm that appears to stretch toward us. The galaxy’s far side sports a few wisps of gas and stars, but it lacks a similarly impressive spiral arm.
This Hubble image combines data from three Snapshot observing programs, which are short observations that slotted into time gaps between other proposals. One of the three programs targeted Arp 184 for its peculiar appearance. This program surveyed galaxies listed in the Atlas of Peculiar Galaxies as well as A Catalogue of Southern Peculiar Galaxies and Associations, a similar catalog compiled by Halton Arp and Barry Madore.
The remaining two Snapshot programs looked at the aftermath of fleeting astronomical events like supernovae and tidal disruption events — like when a supermassive black hole rips a star apart after it wanders too closely. Since Arp 184 hosted four known supernovae in the past three decades, it is a rich target for a supernova hunt.
Image credit: ESA/Hubble & NASA, J. Dalcanton, R. J. Foley (UC Santa Cruz), C. Kilpatrick
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Explore This Section Webb News Latest News Latest Images Webb’s Blog 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 6 Min Read NASA’s Webb Lifts Veil on Common but Mysterious Type of Exoplanet
This artist’s concept shows what the hot sub-Neptune exoplanet TOI-421 b could look like. It is based on spectroscopic data gathered by Webb, as well as previous observations from other telescopes on the ground and in space. Credits:
Illustration: NASA, ESA, CSA, Dani Player (STScI) Though they don’t orbit around our Sun, sub-Neptunes are the most common type of exoplanet, or planet outside our solar system, that have been observed in our galaxy. These small, gassy planets are shrouded in mystery…and often, a lot of haze. Now, by observing exoplanet TOI-421 b, NASA’s James Webb Space Telescope is helping scientists understand sub-Neptunes in a way that was not possible prior to the telescope’s launch.
“I had been waiting my entire career for Webb so that we could meaningfully characterize the atmospheres of these smaller planets,” said principal investigator Eliza Kempton of the University of Maryland, College Park. “By studying their atmospheres, we’re getting a better understanding of how sub-Neptunes formed and evolved, and part of that is understanding why they don’t exist in our solar system.”
Image A: Artist’s Concept of TOI-421 b
This artist’s concept shows what the hot sub-Neptune exoplanet TOI-421 b could look like. It is based on spectroscopic data gathered by Webb, as well as previous observations from other telescopes on the ground and in space. Illustration: NASA, ESA, CSA, Dani Player (STScI) Small, Cool, Shrouded in Haze
The existence of sub-Neptunes was unexpected before they were discovered by NASA’s retired Kepler space telescope in the last decade. Now, astronomers are trying to understand where these planets came from and why are they so common.
Before Webb, scientists had very little information on them. While sub-Neptunes are a few times larger than Earth, they are still much smaller than gas-giant planets and typically cooler than hot Jupiters, making them much more challenging to observe than their gas-giant counterparts.
A key finding prior to Webb was that most sub-Neptune atmospheres had flat or featureless transmission spectra. This means that when scientists observed the spectrum of the planet as it passed in front of its host star, instead of seeing spectral features – the chemical fingerprints that would reveal the composition of the atmosphere – they saw only a flat-line spectrum. Astronomers concluded from all of those flat-line spectra that at least certain sub-Neptunes were probably very highly obscured by either clouds or hazes.
Image B: Spectrum of TOI-421 b
A transmission spectrum captured by NASA’s James Webb Space Telescope reveals chemicals in the atmosphere of the hot sub-Neptune exoplanet TOI-421 b. Illustration: NASA, ESA, CSA, Joseph Olmsted (STScI) A Different Kind of Sub-Neptune?
“Why did we observe this planet, TOI-421 b? It’s because we thought that maybe it wouldn’t have hazes,” said Kempton. “And the reason is that there were some previous data that implied that maybe planets over a certain temperature range were less enshrouded by haze or clouds than others.”
That temperature threshold is about 1,070 degrees Fahrenheit. Below that, scientists hypothesized that a complex set of photochemical reactions would occur between sunlight and methane gas, and that would trigger the haze. But hotter planets shouldn’t have methane and therefore perhaps shouldn’t have haze.
The temperature of TOI-421 b is about 1,340 degrees Fahrenheit, well above the presumed threshold. Without haze or clouds, researchers expected to see a clear atmosphere – and they did!
A Surprising Finding
“We saw spectral features that we attribute to various gases, and that allowed us to determine the composition of the atmosphere,” said the University of Maryland’s Brian Davenport, a third-year Ph.D. student who conducted the primary data analysis. “Whereas with many of the other sub-Neptunes that had been previously observed, we know their atmospheres are made of something, but they’re being blocked by haze.”
The team found water vapor in the planet’s atmosphere, as well as tentative signatures of carbon monoxide and sulfur dioxide. Then there are molecules they didn’t detect, such as methane and carbon dioxide. From the data, they can also infer that a large amount of hydrogen is in TOI-421 b’s atmosphere.
The lightweight hydrogen atmosphere was the big surprise to the researchers. “We had recently wrapped our mind around the idea that those first few sub-Neptunes observed by Webb had heavy-molecule atmospheres, so that had become our expectation, and then we found the opposite,” said Kempton. This suggests TOI-421 b may have formed and evolved differently from the cooler sub-Neptunes observed previously.
Is TOI-421 b Unique?
The hydrogen-dominated atmosphere is also interesting because it mimics the composition of TOI-421 b’s host star. “If you just took the same gas that made the host star, plopped it on top of a planet’s atmosphere, and put it at the much cooler temperature of this planet, you would get the same combination of gases. That process is more in line with the giant planets in our solar system, and it is different from other sub-Neptunes that have been observed with Webb so far,” said Kempton.
Aside from being hotter than other sub-Neptunes previously observed with Webb, TOI-421 b orbits a Sun-like star. Most of the other sub-Neptunes that have been observed so far orbit smaller, cooler stars called red dwarfs.
Is TOI-421b emblematic of hot sub-Neptunes orbiting Sun-like stars, or is it just that exoplanets are very diverse? To find out, the researchers would like to observe more hot sub-Neptunes to determine if this is a unique case or a broader trend. They hope to gain insights into the formation and evolution of these common exoplanets.
“We’ve unlocked a new way to look at these sub-Neptunes,” said Davenport. “These high-temperature planets are amenable to characterization. So by looking at sub-Neptunes of this temperature, we’re perhaps more likely to accelerate our ability to learn about these planets.”
The team’s findings appear on May 5 in 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 CSA (Canadian Space Agency).
To learn more about Webb, visit:
https://science.nasa.gov/webb
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Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Ann Jenkins – jenkins@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Hannah Braun – hbraun@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Related Information
Webb Blog: Reconnaissance of Potentially Habitable Worlds with NASA’s Webb
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