Hubble Survey Sets Up Roman’s Future Look Near Milky Way’s Center
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Hubble Survey Sets Up Roman’s Future Look Near Milky Way’s Center This VISTA VVV Survey image shows the galactic bulge near Sagittarius A*, the supermassive black hole at the Milky Way’s center. A region planned for observation by NASA’s Nancy Grace Roman Space Telescope is outlined. This area has been observed by NASA’s Hubble Space Telescope. Image: NASA, Alyssa Pagan (STScI); Acknowledgment: VISTA, Dante Minniti (UNAB), Ignacio Toledo (ALMA), Martin Kornmesser (ESO)
The Milky Way’s galactic bulge, the bulbous region that surrounds the galactic center, contains a dense collection of stars, planets, and other free-floating objects. This region has been studied for decades with numerous ground-based and space-based telescopes, including NASA’s Hubble and James Webb space telescopes. Soon, NASA’s Nancy Grace Roman Space Telescope will be the first to make studying the galactic bulge a part of its core science objectives, building on the data collected from all observatories before it. Roman’s field of view will cover more area at a far faster cadence than previous space telescopes, allowing it to survey millions of stars and find thousands of new exoplanets.
To support Roman in characterizing numerous stars and planets, astronomers sought to use Hubble to observe many of the same areas of the galactic bulge that Roman will observe in its core Galactic Bulge Time-Domain Survey. By comparing Hubble data taken months or years earlier to new Roman data, astronomers will be better able to interpret Roman’s forthcoming observations. The Roman telescope team is targeting as soon as early September 2026 for launch.
“A top priority of our Hubble survey is to cover as much sky area as possible,” said Sean Terry, project lead and assistant research scientist from the University of Maryland, College Park and NASA’s Goddard Space Flight Center in Greenbelt.
A paper about the team’s work published May 11, 2026 in the Astrophysical Journal.
‘Small’ lenses, large discoveriesMany planetary systems within the Milky Way evolve much like our solar system did, beginning with the collapse of a cosmic gas cloud, the growth of a star, and the formation of surrounding planets. However, in some systems, different events can result in a planet being ejected from the system where it formed. Hundreds of these “rogue planets” will be detected by Roman’s Galactic Bulge Time-Domain Survey, in addition to previously unseen, isolated neutron stars, and even black holes with masses similar to our Sun.
This survey consists of six 72-day observing seasons during which Roman will take a snapshot every 12 minutes of a large portion of the bulge (approximately 1.7 square degrees of the region, or the area of 8.5 full moons). While it will detect a variety of targets, the survey is optimized to look for a specific type of event known as microlensing.
Microlensing events, a type of gravitational lensing event, occur when the light from a more distant object is warped by the mass of a closer object along the line of sight. These events occur on a much smaller scale than larger lensing events (on the order of individual stars instead of galaxies or galaxy clusters) and allow us to search for exoplanets between us and the densely packed stars within the galactic bulge.
“The great thing about microlensing is that we’ll be able to do a complete census of objects as small as Mars that are moving between us and these fields in the bulge, no matter what it is,” said co-author Jay Anderson of the Space Telescope Science Institute in Baltimore.
For Roman, from HubbleWhen a telescope observes a lensing object, such as a bright star, aligning with a star in the galactic bulge, it can be difficult for astronomers to decipher which of the two the starlight comes from. Therefore, timing is a key consideration. If astronomers can identify light sources separately before a microlensing event occurs, it becomes far easier to disentangle them.
To collect this pre-Roman data, astronomers used the Hubble Space Telescope to conduct a large-scale survey, which began in the spring of 2025, covering much of the same area that Roman will observe in the Galactic Bulge Time-Domain Survey. The size of this program is even larger than two previous surveys (each around 0.5 square degrees) that led to Hubble’s largest mosaic, that of our neighboring Andromeda galaxy, which took over 10 years to assemble.
“The main goal of these observations is to be able to identify objects that participate in lensing events during the Roman survey, catching them before they undergo the lensing event,” said Anderson. “When, in a couple of years, an event happens during Roman’s long stare at the field, we can go back and say, ‘This was a red star, this was a blue star, and the event happened when the red star went in front of the blue star.’”
The data from Hubble also will help shape the analysis of the lensing objects themselves. The microlensing event itself measures only a ratio of the masses of a host star and its planet. With data from stars before or after their microlensing events, however, scientists would be able to measure the stars’ individual masses, echoing the way Hubble previously determined the mass of a star and its planet in the Milky Way. This method turns a more opaque measurement of the relationship between a star and its planet into one far more certain.
“Instead of estimating a mass ratio of a planet that’s orbiting a star, we can say that we’re confident it’s a Saturn-mass planet orbiting a star that’s 0.8 solar masses, for example,” Terry said. “So with the help of precursor imaging from Hubble you can hope to get direct measurements of the masses as opposed to indirect mass ratios.”
Next leap in magnitudeWhile exoplanet discovery is a large part of Roman’s Galactic Bulge Time-Domain Survey, observing such a large area with Hubble also can help identify areas of extinction, dense pockets of dust and gas that absorb or scatter light, allowing us to create maps detailing where we can see stars and where we can’t.
Hubble’s survey also has provided the crucial beginning of a brand-new catalog of stars, which will help astronomers characterize the host stars of exoplanets discovered by Roman. The research team predicts Roman will add to Hubble’s star catalog by an order of magnitude.
“This Hubble survey will build a catalog of 20 to 30 million point sources,” said Terry. “But, by the end of the Galactic Bulge Time-Domain Survey, Roman may measure about 200 to 300 million, and it will produce, essentially, some of the deepest images ever taken of any part of the sky.”
The data from the most recent Hubble survey is available in the Mikulski Archive for Space Telescopes.
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 Goddard 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.
The Nancy Grace Roman Space Telescope is managed at NASA Goddard with participation by NASA’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute; and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems, Inc. in Boulder, Colorado; L3Harris Technologies in Melbourne, Florida; and Teledyne Scientific & Imaging in Thousand Oaks, California.
Related Images & Videos Hubble/Roman Galactic Bulge Survey Region (VISTA VVV Survey)This VISTA VVV Survey image shows the galactic bulge near Sagittarius A*, the supermassive black hole at the Milky Way’s center. A region planned for observation by NASA’s Nancy Grace Roman Space Telescope is outlined. This area has been observed by NASA’s Hubble Space Telescope.
Microlensing Event at OGLE-2013-BLG-0341 (Hubble Image)
A follow-up observation by NASA’s Hubble Space Telescope shows a region containing a microlensing event captured by the Optical Gravitational Lensing Experiment (OGLE) in 2013. Hubble was able to separate the foreground lens from the background star.
Microlensing Infographic
This graphic illustrates a microlensing event, which occurs when the light from a distant object warps as a mass, such as a foreground star, precisely aligns in front of that object. This causes the more distant background star to increase in apparent brightness.
Zoom Into the Milky Way’s Galactic Bulge – Hubble/Roman Survey Regions
This video shows a zoom into the Milky Way’s galactic bulge near the galactic center. As it zooms in, the view changes from the near-infrared 2MASS survey to the VISTA VVV survey (both ground-based).
Claire Andreoli
NASA’s Goddard Space Flight Center
Greenbelt, Maryland
claire.andreoli@nasa.gov
Matthew Brown, Christine Pulliam
Space Telescope Science Institute
Baltimore, Maryland
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Cosmology with the Nancy Grace Roman Space Telescope
NASA’s Psyche Mission Captures Mars During Gravity Assist Approach
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This colorized image of Mars was captured by NASA’s Psyche mission on May 3, 2026, about 3 million miles (4.8 million kilometers) from the planet. The spacecraft is approaching the planet for a gravity assist on May 15 that will give it a boost in speed and adjust its trajectory toward asteroid Psyche for eventual arrival in 2029.
The spacecraft is approaching Mars from a high-phase angle, meaning that the planet appears only as a thin crescent, like our own crescent Moon seen around its new Moon phase. From this viewing geometry, the Sun is out of frame and “above” both Mars and Psyche.
Figure A
Figure A is a zoomed-out view from the imager. No stars are visible in the background since they are much dimmer than the sunlight being reflected by Mars.
The observation was acquired by the multispectral imager instrument’s panchromatic or broadband filter, with an exposure time of just 2 milliseconds. Even with this very short exposure time, the crescent is extremely bright and parts of the image are oversaturated. The light seen here is sunlight reflected off the surface of Mars and also scattered by dust particles in its atmosphere. Because the quantity of dust in the atmosphere can vary rapidly over time, the anticipated brightness of the crescent was hard to predict before this early image was acquired.
The dustiness of Mars leads to sunlight being scattered by its atmosphere, making the crescent appear to extend farther around the planet than if it had no atmosphere (as with our Moon).Of note, on the right side of the extended crescent, there appears to be a gap, which coincides with the planet’s icy north polar cap. The cap is currently in winter and mission specialists hypothesize that seasonal clouds and hazes may be forming in that region, possibly blocking the atmospheric dust’s ability to scatter sunlight like it does elsewhere around the planet.
The Psyche mission’s imager team will be acquiring, processing, and interpreting similar images in the lead-up to the close approach on May 15. The images are primarily designed to calibrate the cameras and to characterize their performance in flight as a practice run for the approach to asteroid Psyche in 2029.
For more information about the Psyche mission, read: https://science.nasa.gov/mission/psyche/
Keep Exploring Discover More Topics From PhotojournalExtreme galaxy-scale outflows are frequent among luminous early quasars
Nature, Published online: 06 May 2026; doi:10.1038/s41586-026-10477-9
James Webb Space Telescope observations show powerful high-redshift quasar outflows, supporting quasar feedback as a key mechanism driving rapid star-formation quenching in early massive galaxies.Unlocking the Mystery of X-ray Dots
A new “X-ray dot” found by NASA’s Chandra X-ray Observatory – which could look like this artist’s illustration released on April 28, 2026 – could explain what the hundreds or potentially thousands of these objects are.
Shortly after NASA’s James Webb Space Telescope started its science observations, reports of a new class of mysterious objects emerged. Astronomers found small, red objects about 12 billion light-years from Earth or farther, which became known as “little red dots” (LRDs). The dot that Chandra found exhibits most of the features of an LRD, including being small, red, and located at a vast distance, but it glows in X-ray light, unlike other LRDs – hence the name “X-ray dot.”
This object (officially known as 3DHST-AEGIS-12014), which is located about 11.8 billion light-years from Earth, may provide a crucial bridge between black hole stars and typical growing supermassive black holes.
Read more about this mysterious dot.
Image credit: NASA/CXC/SAO/M. Weiss; adapted by K. Arcand & J. Major
NASA’s Roman Poised to Transform Hunt for Elusive Neutron Stars
Astronomers have long known that neutron stars, the crushed cores left behind after massive stars explode, should be scattered throughout the Milky Way galaxy. However, most of them are effectively invisible. A new study published in Astronomy and Astrophysics suggests NASA’s upcoming Nancy Grace Roman Space Telescope could spot them anyway.
Using detailed simulations of the Milky Way and Roman’s future observations, researchers showed the flagship observatory may be able to identify and characterize dozens of isolated neutron stars through a subtle effect called gravitational microlensing.
“Most neutron stars are relatively dim and on their own,” said Zofia Kaczmarek of Heidelberg University in Germany, who led the study. “They are incredibly hard to spot without some sort of help.”
Finding what’s invisibleNeutron stars pack more mass than the Sun into a sphere about the size of a city. Studying them helps us understand how stars live, die, and spread heavy elements throughout the universe. They also provide a chance to study what happens under the most extreme conditions (pressures and densities) imaginable.
Yet, unless they are pulsars that beam in radio wavelengths or glow in X-rays, they can remain hidden from even the most powerful telescopes.
Roman can search for them in a different way. When a massive object like a neutron star moves in front of a distant background star, its intense gravity warps spacetime and deflects the background star’s light. This microlensing effect briefly makes the background star brighter and appear offset from its true position in the sky.
While many telescopes can detect the temporary brightening, Roman can measure both the brightening (photometry) and the tiny positional shift (astrometry) of the lensed star with exceptional precision.
Astrometric microlensing occurs when a foreground object, like a neutron star, passes in front of a more distant background star. The neutron star’s gravity bends the distant star’s light, splitting it into multiple paths that reach the telescope. Although these distorted images can’t be resolved, their combined light appears brighter and slightly shifted from the distant star’s true position. As the alignment between the two objects changes over time, this apparent shift traces a small elliptical pattern on the sky. The size of that ellipse depends on how strongly the light is bent, meaning more massive objects produce larger shifts, allowing astronomers to directly measure the mass of the otherwise invisible neutron star.NASA, STScI, Joyce Kang (STScI)
Because neutron stars are relatively massive, they produce a larger astrometric signal than lighter objects, allowing missions like Roman to not only detect them, but also weigh them in some cases, something that is nearly impossible with photometry alone.
“What’s really cool about using microlensing is that you can get direct mass measurements,” said paper co-author Peter McGill of Lawrence Livermore National Laboratory. “Photometry tells us that something passed in front of the star, but it’s the amount the star’s position shifts that tells us how massive that object is. By measuring that tiny deflection on the sky, we can directly weigh something that is otherwise unseen.”
Roman’s measurements could help astronomers determine whether there is a true gap between the masses of neutron stars and black holes and how fast neutron stars are moving.
Scientists are particularly interested in understanding the powerful “kicks” neutron stars receive when they are born in supernova explosions. These kicks can send them racing through the galaxy at hundreds of miles per second.
Huge surveys, high chance of payoffThe research team will utilize Roman’s future Galactic Bulge Time Domain Survey, which will monitor millions of stars at a time in vast images of the sky, taken at a high frequency.
“We’re going to get to work as soon as the data start coming in,” said McGill. “Even in the first months after commissioning, we expect to start identifying promising events.”
Even a relatively small number of confirmed detections could significantly improve models of stellar explosions and extreme matter.
“We don’t know the mass distribution of neutron stars, black holes, or where one ends and the other begins with any certainty,” McGill said. “Roman will really be a breakthrough in that.”
Although only a few thousand neutron stars have been detected so far, mostly as pulsars, scientists estimate there could be tens of millions to hundreds of millions in the Milky Way. Additionally, to date, researchers have only been able to measure the masses of neutron stars in binary pairings.
“We’re seeing a small sample that’s not representative of the big picture,” Kaczmarek said. “Even a single mass measurement would be very powerful. If we found just one isolated neutron star, it would already be incredibly stimulating to our research.”
Looking aheadThe study also highlights a creative use of the mission’s capabilities. While Roman’s survey is designed primarily to find exoplanets using photometric microlensing, its powerful astrometric capabilities open the door to entirely new discoveries with astrometric microlensing.
“This wasn’t part of the original plan,” said McGill. “But it turns out Roman’s astrometric capability is really good at detecting neutron stars and black holes, so we can add a whole new kind of science to Roman’s surveys.”
If the predictions hold true, the mission could provide the first large sample of isolated neutron stars discovered through their gravity alone, revealing a hidden population that has remained out of reach until now. Roman is expected to transform the study of microlensing and the hidden populations of objects in our galaxy, from rogue exoplanets to stellar remnants like neutron stars.
The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute in Baltimore; and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems Inc. in Boulder, Colorado; L3Harris Technologies in Rochester, New York; and Teledyne Scientific & Imaging in Thousand Oaks, California.
To learn more about Roman visit:
By Hannah Braun
Space Telescope Science Institute, Baltimore, Md.
hbraun@stsci.edu
Media contacts:
Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, Md.
301-286-1940
Christine Pulliam
Space Telescope Science Institute, Baltimore, Md.
cpulliam@stsci.edu
NASA Volunteers Double Known Population of Brown Dwarfs
A new paper from NASA’s Backyard Worlds: Planet 9 project announces that volunteers have essentially doubled the number of known brown dwarfs, with over 3,000 new discoveries made over the past 10 years since the project began. Brown dwarfs are balls of gas the size of Jupiter, less massive than stars. There’s one for every three or four stars near the Sun.
Although brown dwarfs are common, they can be hard to spot because they shine so faintly compared to stars. Having twice as many brown dwarfs to study allows astronomers a deeper understanding of these elusive objects. Already, this vital new list of brown dwarfs has revealed a new variety of objects – the extreme T subdwarfs and many other rarities, such as ultra-cool objects and a brown dwarf that appears to have aurorae. It has also helped us inventory the distribution of mass in our galaxy and map our cosmic neighborhood.
The discoveries are published in a paper published in the Astronomical Journal, led by astronomer Adam Schneider from the U.S. Naval Observatory. They represent work done over the course of ten years aided by a team of roughly 200,000 volunteers. Of the paper’s 75 authors, 61 are volunteers. Two of the other authors began their work with the team as volunteers and then embarked on careers in astronomy.
“I truly appreciate the recognition for all of us who collaborated, in some way, on this effort,” said Walter Ruben Robledo, an amateur astronomer and Backyard Worlds: Planet 9 volunteer from Cordoba, Argentina.
“When I received the news about the co-authorship, I thought: Yes, dreams do come true,” said another volunteer, Mayahuel Torres Guerrero, from Mexico City.
The volunteers discovered these brown dwarfs in images taken by NASA’s retired Wide-field Infrared Survey Explorer (WISE) and Near-Earth-Object WISE Reactivation mission (NEOWISE-R). They examined the data using the Zooniverse citizen science platform, searching for moving objects by blinking images taken over a 16-year time period. Some volunteers even contributed by building their own search tools and data analysis software.
Want to help make the next brown dwarf discovery? The Backyard Worlds: Planet 9 project is still sifting through more than 2 billion sources seen by WISE and NEOWISE-R. Join the search at backyardwords.org.
Artist’s concept of a brown dwarf by Backyard Worlds: Planet 9 volunteer William Pendrill. The Backyard Worlds: Planet 9 project announced the discovery of more than 3,000 of these objects over the past 10 years, doubling the number known. Join the search at backyardworlds.org! Credit: William Pendrill Learn More and Get Involved Backyard Worlds: Planet 9
Search the realm beyond Neptune for new planets, nearby stars and more. For anyone with a smartphone or laptop.
Facebook logo @nasascience_ @nasascience_ Instagram logo @nasascience_ Linkedin logo @nasascience_ Share Details Last Updated May 05, 2026 Related Terms Explore More 4 min read For NASA’s TESS, Stellar Eclipses Shed Light on Possible New Worlds
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For NASA’s TESS, Stellar Eclipses Shed Light on Possible New WorldsA study of NASA’s TESS (Transiting Exoplanet Survey Satellite) data on stellar pairs undergoing mutual eclipses has uncovered more than two dozen candidate exoplanets, or worlds beyond our solar system. This method allows the mission to locate planets it couldn’t otherwise detect.
A gas giant planet looms in the foreground at right, illuminated by a pair of stars, in this artist’s concept of a world in a binary system. NASA’s TESS (Transiting Exoplanet Survey Satellite) has found planets in two binary star systems by looking for stellar dimming as the planets cross in front of one of the stars. Astronomers have now demonstrated a new method of finding planets in these systems by focusing on the timing of the stars’ mutual eclipses. NASA’s Goddard Space Flight Center/Chris Smith (USRA)
To date, TESS has discovered 885 confirmed exoplanets and identified more than 7,900 candidates, nearly all found because the planets pass in front of their stars from our perspective. These events, called transits, produce a small, regular dip in the brightness of the planet’s host star. TESS also observes tens of thousands of eclipsing binary stars — two orbiting stars that alternately eclipse each other from our vantage point. Astronomers can detect the gravitational tug of exoplanets in these systems by carefully measuring the exact timing of many eclipses. Prior to the new study, discoveries by NASA’s retired Kepler mission and other facilities had recorded 16 transiting worlds around binary stars, while TESS had found an additional two.
“Identifying transits in binary systems clearly is challenging, but we’d like to know more about the range of planets that can form around two gravitationally bound stars,” said study lead Margo Thornton, a doctoral candidate at UNSW (University of New South Wales) in Sydney. “So we developed a survey to search for planets using stellar eclipses that is not limited to the orientation of the planet’s orbit.”
A paper describing the findings published May 4 in the journal Monthly Notices of the Royal Astronomical Society.
For planets located in binary systems, the orientation of the planet’s orbit can tell us about how that system formed. Some models of planet formation in binary systems suggest planets mainly form near the plane formed by the two orbiting stars, increasing the likelihood of binaries hosting transiting worlds. But other models indicate a much more disorderly formation process, with the stellar pair stirring its young planets into wider and more tilted paths much less likely to undergo transits.
The timing of stellar eclipses can gradually change through tidal and rotational interactions between the stars, the effects of general relativity, and the presence of other unseen masses, such as planets, in the system. All of these forces cause the entire orbital plane of the binary to rotate, or precess, and this in turn alters the eclipse timing.
“The key to calculating all of these different influences is the long, rich set of observations available from TESS,” said co-author Benjamin Montet, a Scientia associate professor at UNSW Sydney. “After analyzing 1,590 binaries with at least two years of TESS data, we found 27 with candidate planets that now await confirmation.”
Explore how observations of stellar eclipses can expand the capabilities of NASA’s TESS, leading to the discovery of new candidate planets it couldn’t otherwise detect. NASA’s Goddard Space Flight Center/Francis Reddy
Since science operations began in 2018, TESS has tiled the sky by observing large swaths, called sectors, for nearly a month. Currently, the mission’s cameras capture a single image of the entire sector, measuring 24 by 96 degrees, about every 3 minutes, with even faster observations of selected targets.
The masses of the new candidates remain uncertain, but the team estimates the smallest world may hold as little 12 Earth masses, with the largest topping out around 3,200 Earths, or about 10 times Jupiter’s mass. Confirming these planets will require future ground-based observations that precisely measure the velocities of the host stars, which will reveal the slight gravitational tugs of any possible planets.
“The TESS mission was built to find transiting planets, and it’s great to see how the same measurements are driving discoveries far beyond its original mission,” said Allison Youngblood, the TESS project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The mission’s continuing data collection is a treasure trove that enables new findings across a wide range of astronomical topics, from asteroids in the solar system to active galaxies powered by black holes in the distant universe.”
You could discover the next exoplanet! Join the Planet Hunters TESS citizen science project, and you’ll learn how to read light curves — plots of light data from distant stars — to find telltale signals from orbiting exoplanets.
By Francis Reddy
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Media Contact:
Claire Andreoli
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NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Share Details Last Updated May 04, 2026 Related TermsHubble Spots a Starry Spiral
In this new picture from NASA’s Hubble Space Telescope, a spiral galaxy glittering with star clusters is the center of attention. NGC 3137 is located 53 million light-years away in the constellation Antlia (the Air Pump). As a nearby spiral galaxy, this target offers astronomers an excellent opportunity to study the cycle of stellar birth and death, as well as giving researchers a glimpse of a galactic system similar to our own.
NGC 3137 is of particular interest to astronomers because it travels through space with a group of galaxies that is thought to be similar to the Local Group, the galaxy group that contains our Milky Way. Similar to the Local Group, the NGC 3175 group contains two large spiral galaxies: NGC 3137 and NGC 3175, which Hubble has also observed. In the Local Group, the largest members are the Milky Way galaxy and Andromeda, another spiral galaxy. In addition to two large spiral galaxies, both groups also contain a number of smaller dwarf galaxies, although it’s not yet known how many of these tiny companions the NGC 3175 group has; researchers have found more than 500 dwarf galaxy candidates. By studying this nearby galaxy group, astronomers can learn about the dynamics of our own galactic home.
Image credit: ESA/Hubble & NASA, D. Thilker and the PHANGS-HST Team
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NASA Connects Little Red Dots with Chandra, Webb
A newly discovered object may be a key to unlocking the true nature of a mysterious class of sources that astronomers have found in the early universe in recent years.
A “X-ray dot” found by NASA’s Chandra X-ray Observatory could explain what the hundreds or potentially thousands of these objects are. A paper describing the results published in The Astrophysical Journal Letters.
Shortly after NASA’s James Webb Space Telescope started its science observations, reports of a new class of mysterious objects emerged. Astronomers found small, red objects about 12 billion light-years from Earth or farther, which became known as “little red dots” (LRDs).
Many scientists think LRDs are supermassive black holes embedded in clouds of dense gas, which mask some of the typical signatures in different kinds of light – including X-rays – that astronomers usually use to identify them. This would make them different from typical growing supermassive black holes, which are not embedded in dense gas, allowing bright ultraviolet light and X-rays from material orbiting the black holes to escape.
Because of this and their potential similarities to stellar atmospheres, astronomers have called this the “black hole star” scenario for LRDs.
This new “X-ray dot” (officially known as 3DHST-AEGIS-12014), which is located about 11.8 billion light-years from Earth, may provide a crucial bridge between black hole stars and typical growing supermassive black holes. It exhibits most of the features of an LRD, including being small, red, and located at a vast distance, but it glows in X-ray light, unlike other LRDs.
“Astronomers have been trying to figure out what little red dots are for several years,” said lead author Raphael Hviding of the Max Planck Institute for Astronomy in Germany. “This single X-ray object may be – to use a phrase – what lets us connect all of the dots.”
Artist’s Illustration of a Close-Up View of X-ray Dot, 3DHST-AEGIS-12014. NASA/CXC/SAO/M. Weiss; adapted by K. Arcand & J. Major
The team found this one special object after comparing new data from Webb with a deep survey previously performed by Chandra.
“If little red dots are rapidly growing supermassive black holes, why do they not give off X-rays like other such black holes?” said co-author Anna de Graaff of the Center for Astrophysics | Harvard & Smithsonian, in Cambridge, Massachusetts. “Finding a little red dot that looks different from the others gives us important new insight into what could power them.”
The researchers suggest that the X-ray dot represents a transition phase from an LRD to a typical growing supermassive black hole. As the black hole star consumes its surrounding gas, patchy holes in the clouds of gas appear. This allows X-rays from material falling onto the black hole to poke through, which are observed by Chandra. Eventually all the gas is consumed, and the black hole star ceases to exist.
There are also hints in the Chandra data of the X-ray dot that there are variations in X-ray brightness, which supports the idea that the black hole is partly obscured. As the cloud of gas rotates, patches of denser and less dense gas can move across the black hole, causing changes in X-ray brightness.
“If we confirm the X-ray dot as a little red dot in transition, not only would it be the first of its kind, but we may be seeing into the heart of a little red dot for the first time,” said co-author Hanpu Liu of Princeton University in New Jersey. “We would also have the strongest piece of evidence yet that the growth of supermassive black holes is at the center of some, if not all, of the little red dot population.”
An alternate idea for the X-ray dot is that it is a more common type of growing supermassive black hole but is veiled in an exotic type of dust that astronomers have not seen before. Future observations are planned that should be able to shed light on the truth.
“The X-ray dot had been sitting in our Chandra survey data for over ten years, but we had no idea how remarkable it was before Webb came along to observe the field,” said co-author Andy Goulding of Princeton. “This is a powerful example of collaboration between two great observatories.”
NASA’s Marshall Space Flight Center 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.
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joel.w.wallace@nasa.gov
Student uses space cosmic rays to make photographs
Why cosmology is more than a theory
Nature, Published online: 27 April 2026; doi:10.1038/d41586-026-01303-3
A philosophical take on the history of the Universe that is inspiring but incomplete.