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Webb 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 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 Newfound Galaxy Class May Indicate Early Black Hole Growth, Webb Finds
A team of astronomers sifted through James Webb Space Telescope data from multiple surveys to compile one of the largest samples of “little red dots” to date. Credits:
NASA, ESA, CSA, STScI, Dale Kocevski (Colby College). In December 2022, less than six months after commencing science operations, NASA’s James Webb Space Telescope revealed something never seen before: numerous red objects that appear small on the sky, which scientists soon called “little red dots” (LRDs). Though these dots are quite abundant, researchers are perplexed by their nature, the reason for their unique colors, and what they convey about the early universe.
A team of astronomers recently compiled one of the largest samples of LRDs to date, nearly all of which existed during the first 1.5 billion years after the big bang. They found that a large fraction of the LRDs in their sample showed signs of containing growing supermassive black holes.
“We’re confounded by this new population of objects that Webb has found. We don’t see analogs of them at lower redshifts, which is why we haven’t seen them prior to Webb,” said Dale Kocevski of Colby College in Waterville, Maine, and lead author of the study. “There’s a substantial amount of work being done to try to determine the nature of these little red dots and whether their light is dominated by accreting black holes.”
Image A: Little Red Dots (NIRCam Image)
A team of astronomers sifted through James Webb Space Telescope data from multiple surveys to compile one of the largest samples of “little red dots” to date. From their sample, they found that these mysterious red objects that appear small on the sky emerge in large numbers around 600 million years after the big bang and undergo a rapid decline in quantity around 1.5 billion years after the big bang. NASA, ESA, CSA, STScI, Dale Kocevski (Colby College). A Potential Peek Into Early Black Hole Growth
A significant contributing factor to the team’s large sample size of LRDs was their use of publicly available Webb data. To start, the team searched for these red sources in the Cosmic Evolution Early Release Science (CEERS) survey before widening their scope to other extragalactic legacy fields, including the JWST Advanced Deep Extragalactic Survey (JADES) and the Next Generation Deep Extragalactic Exploratory Public (NGDEEP) survey.
The methodology used to identify these objects also differed from previous studies, resulting in the census spanning a wide redshift range. The distribution they discovered is intriguing: LRDs emerge in large numbers around 600 million years after the big bang and undergo a rapid decline in quantity around 1.5 billion years after the big bang.
The team looked toward the Red Unknowns: Bright Infrared Extragalactic Survey (RUBIES) for spectroscopic data on some of the LRDs in their sample. They found that about 70 percent of the targets showed evidence for gas rapidly orbiting 2 million miles per hour (1,000 kilometers per second) – a sign of an accretion disk around a supermassive black hole. This suggests that many LRDs are accreting black holes, also known as active galactic nuclei (AGN).
“The most exciting thing for me is the redshift distributions. These really red, high-redshift sources basically stop existing at a certain point after the big bang,” said Steven Finkelstein, a co-author of the study at the University of Texas at Austin. “If they are growing black holes, and we think at least 70 percent of them are, this hints at an era of obscured black hole growth in the early universe.”
Contrary to Headlines, Cosmology Isn’t Broken
When LRDs were first discovered, some suggested that cosmology was “broken.” If all of the light coming from these objects was from stars, it implied that some galaxies had grown so big, so fast, that theories could not account for them.
The team’s research supports the argument that much of the light coming from these objects is from accreting black holes and not from stars. Fewer stars means smaller, more lightweight galaxies that can be understood by existing theories.
“This is how you solve the universe-breaking problem,” said Anthony Taylor, a co-author of the study at the University of Texas at Austin.
Curiouser and Curiouser
There is still a lot up for debate as LRDs seem to evoke even more questions. For example, it is still an open question as to why LRDs do not appear at lower redshifts. One possible answer is inside-out growth: As star formation within a galaxy expands outward from the nucleus, less gas is being deposited by supernovas near the accreting black hole, and it becomes less obscured. In this case, the black hole sheds its gas cocoon, becomes bluer and less red, and loses its LRD status.
Additionally, LRDs are not bright in X-ray light, which contrasts with most black holes at lower redshifts. However, astronomers know that at certain gas densities, X-ray photons can become trapped, reducing the amount of X-ray emission. Therefore, this quality of LRDs could support the theory that these are heavily obscured black holes.
The team is taking multiple approaches to understand the nature of LRDs, including examining the mid-infrared properties of their sample, and looking broadly for accreting black holes to see how many fit LRD criteria. Obtaining deeper spectroscopy and select follow-up observations will also be beneficial for solving this currently “open case” about LRDs.
“There’s always two or more potential ways to explain the confounding properties of little red dots,” said Kocevski. “It’s a continuous exchange between models and observations, finding a balance between what aligns well between the two and what conflicts.”
These results were presented in a press conference at the 245th meeting of the American Astronomical Society in National Harbor, Maryland, and have been submitted for publication in The Astrophysical Journal.
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).
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A thick torus of gas and dust surrounding a supermassive black hole is shown in this artist’s concept. The torus can obscure light that’s generated by material falling into the black hole. Observations by NASA telescopes have helped scientists identify more of these hidden black holes.NASA/JPL-Caltech An effort to find some of the biggest, most active black holes in the universe provides a better estimate for the ratio of hidden to unhidden behemoths.
Multiple NASA telescopes recently helped scientists search the sky for supermassive black holes — those up to billions of times heavier than the Sun. The new survey is unique because it was as likely to find massive black holes that are hidden behind thick clouds of gas and dust as those that are not.
Astronomers think that every large galaxy in the universe has a supermassive black hole at its center. But testing this hypothesis is difficult because researchers can’t hope to count the billions or even trillions of supermassive black holes thought to exist in the universe. Instead they have to extrapolate from smaller samples to learn about the larger population. So accurately measuring the ratio of hidden supermassive black holes in a given sample helps scientists better estimate the total number of supermassive black holes in the universe.
The new study published in the Astrophysical Journal found that about 35% of supermassive black holes are heavily obscured, meaning the surrounding clouds of gas and dust are so thick they block even low-energy X-ray light. Comparable searches have previously found less than 15% of supermassive black holes are so obscured. Scientists think the true split should be closer to 50/50 based on models of how galaxies grow. If observations continue to indicate significantly less than half of supermassive black holes are hidden, scientists will need to adjust some key ideas they have about these objects and the role they play in shaping galaxies.
Hidden Treasure
Although black holes are inherently dark — not even light can escape their gravity — they can also be some of the brightest objects in the universe: When gas gets pulled into orbit around a supermassive black hole, like water circling a drain, the extreme gravity creates such intense friction and heat that the gas reaches hundreds of thousands of degrees and radiates so brightly it can outshine all the stars in the surrounding galaxy.
The clouds of gas and dust that surround and replenish the bright central disk may roughly take the shape of a torus, or doughnut. If the doughnut hole is facing toward Earth, the bright central disk within it is visible; if the doughnut is seen edge-on, the disk is obscured.
A supermassive black hole surrounded by a torus of gas and dust is depicted in four different wavelengths of light in this artist’s concept. Visible light (top right) and low-energy X-rays (bottom left) are blocked by the torus; infrared (top left) is scattered and reemitted; and some high energy X-rays (bottom right) can penetrate the torus. NASA/JPL-Caltech Most telescopes can rather easily identify face-on supermassive black holes, though not edge-on ones. But there’s an exception to this that the authors of the new paper took advantage of: The torus absorbs light from the central source and reemits lower-energy light in the infrared range (wavelengths slightly longer than what human eyes can detect). Essentially, the doughnuts glow in infrared.
These wavelengths of light were detected by NASA’s Infrared Astronomical Satellite, or IRAS, which operated for 10 months in 1983 and was managed by NASA’s Jet Propulsion Laboratory in Southern California. A survey telescope that imaged the entire sky, IRAS was able to see the infrared emissions from the clouds surrounding supermassive black holes. Most importantly, it could spot edge-on and face-on black holes equally well.
IRAS caught hundreds of initial targets. Some of them turned out to be not heavily obscured black holes but galaxies with high rates of star formation that emit a similar infrared glow. So the authors of the new study used ground-based, visible-light telescopes to identify those galaxies and separate them from the hidden black holes.
To confirm edge-on, heavily obscured black holes, the researchers relied on NASA’s NuSTAR (Nuclear Spectroscopic Telescope Array), an X-ray observatory also managed by JPL. X-rays are radiated by some of the hottest material around the black hole. Lower-energy X-rays are absorbed by the surrounding clouds of gas and dust, while the higher-energy X-rays observed by NuSTAR can penetrate and scatter off the clouds. Detecting these X-rays can take hours of observation, so scientists working with NuSTAR first need a telescope like IRAS to tell them where to look.
NASA’s NuSTAR X-ray telescope, depicted in this artist’s concept, has helped astronomers get a better sense of how many supermassive black holes are hidden from view by thick clouds of gas and dust that surround them.NASA/JPL-Caltech “It amazes me how useful IRAS and NuSTAR were for this project, especially despite IRAS being operational over 40 years ago,” said study lead Peter Boorman, an astrophysicist at Caltech in Pasadena, California. “I think it shows the legacy value of telescope archives and the benefit of using multiple instruments and wavelengths of light together.”
Numerical Advantage
Determining the number of hidden black holes compared to nonhidden ones can help scientists understand how these black holes get so big. If they grow by consuming material, then a significant number of black holes should be surrounded by thick clouds and potentially obscured. Boorman and his coauthors say their study supports this hypothesis.
In addition, black holes influence the galaxies they live in, mostly by impacting how galaxies grow. This happens because black holes surrounded by massive clouds of gas and dust can consume vast — but not infinite — amounts of material. If too much falls toward a black hole at once, the black hole starts coughing up the excess and firing it back out into the galaxy. That can disperse gas clouds within the galaxy where stars are forming, slowing the rate of star formation there.
“If we didn’t have black holes, galaxies would be much larger,” said Poshak Gandhi, a professor of astrophysics at the University of Southampton in the United Kingdom and a coauthor on the new study. “So if we didn’t have a supermassive black hole in our Milky Way galaxy, there might be many more stars in the sky. That’s just one example of how black holes can influence a galaxy’s evolution.”
More About NuSTAR
A Small Explorer mission led by Caltech and managed by NASA’s Jet Propulsion Laboratory in Southern California for the agency’s Science Mission Directorate in Washington, NuSTAR was developed in partnership with the Danish Technical University and the Italian Space Agency (ASI). The spacecraft was built by Orbital Sciences Corp. in Dulles, Virginia. NuSTAR’s mission operations center is at the University of California, Berkeley, and the official data archive is at NASA’s High Energy Astrophysics Science Archive Research Center at NASA’s Goddard Space Flight Center. ASI provides the mission’s ground station and a mirror data archive. Caltech manages JPL for NASA.
For more information on NuSTAR, visit:
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International teams of astronomers monitoring a supermassive black hole in the heart of a distant galaxy have detected features never seen before using data from NASA missions and other facilities. The features include the launch of a plasma jet moving at nearly one-third the speed of light and unusual, rapid X-ray fluctuations likely arising from near the very edge of the black hole.
Radio images of 1ES 1927+654 reveal emerging structures that appear to be jets of plasma erupting from both sides of the galaxy’s central black hole following a strong radio flare. The first image, taken in June 2023, shows no sign of the jet, possibly because hot gas screened it from view. Then, starting in February 2024, the features emerge and expand away from the galaxy’s center, covering a total distance of about half a light-year as measured from the center of each structure. NSF/AUI/NSF NRAO/Meyer at al. 2025 The source is 1ES 1927+654, a galaxy located about 270 million light-years away in the constellation Draco. It harbors a central black hole with a mass equivalent to about 1.4 million Suns.
“In 2018, the black hole began changing its properties right before our eyes, with a major optical, ultraviolet, and X-ray outburst,” said Eileen Meyer, an associate professor at UMBC (University of Maryland Baltimore County). “Many teams have been keeping a close eye on it ever since.”
She presented her team’s findings at the 245th meeting of the American Astronomical Society in National Harbor, Maryland. A paper led by Meyer describing the radio results was published Jan. 13 in The Astrophysical Journal Letters.
After the outburst, the black hole appeared to return to a quiet state, with a lull in activity for nearly a year. But by April 2023, a team led by Sibasish Laha at UMBC and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, had noted a steady, months-long increase in low-energy X-rays in measurements by NASA’s Neil Gehrels Swift Observatory and NICER (Neutron star Interior Composition Explorer) telescope on the International Space Station. This monitoring program, which also includes observations from NASA’s NuSTAR (Nuclear Spectroscopic Telescope Array) and ESA’s (European Space Agency) XMM-Newton mission, continues.
The increase in X-rays triggered the UMBC team to make new radio observations, which indicated a strong and highly unusual radio flare was underway. The scientists then began intensive observations using the NRAO’s (National Radio Astronomy Observatory) VLBA (Very Long Baseline Array) and other facilities. The VLBA, a network of radio telescopes spread across the U.S., combines signals from individual dishes to create what amounts to a powerful, high-resolution radio camera. This allows the VLBA to detect features less than a light-year across at 1ES 1927+654’s distance.
Active galaxy 1ES 1927+654, circled, has exhibited extraordinary changes since 2018, when a major outburst occurred in visible, ultraviolet, and X-ray light. The galaxy harbors a central black hole weighing about 1.4 million solar masses and is located 270 million light-years away. Pan-STARRS Radio data from February, April, and May 2024 reveals what appear to be jets of ionized gas, or plasma, extending from either side of the black hole, with a total size of about half a light-year. Astronomers have long puzzled over why only a fraction of monster black holes produce powerful plasma jets, and these observations may provide critical clues.
“The launch of a black hole jet has never been observed before in real time,” Meyer noted. “We think the outflow began earlier, when the X-rays increased prior to the radio flare, and the jet was screened from our view by hot gas until it broke out early last year.”
A paper exploring that possibility, led by Laha, is under review at The Astrophysical Journal. Both Meyer and Megan Masterson, a doctoral candidate at the Massachusetts Institute of Technology in Cambridge who also presented at the meeting, are co-authors.
Using XMM-Newton observations, Masterson found that the black hole exhibited extremely rapid X-ray variations between July 2022 and March 2024. During this period, the X-ray brightness repeatedly rose and fell by 10% every few minutes. Such changes, called millihertz quasiperiodic oscillations, are difficult to detect around supermassive black holes and have been observed in only a handful of systems to date.
“One way to produce these oscillations is with an object orbiting within the black hole’s accretion disk. In this scenario, each rise and fall of the X-rays represents one orbital cycle,” Masterson said.
If the fluctuations were caused by an orbiting mass, then the period would shorten as the object fell ever closer to the black hole’s event horizon, the point of no return. Orbiting masses generate ripples in space-time called gravitational waves. These waves drain away orbital energy, bringing the object closer to the black hole, increasing its speed, and shortening its orbital period.
Over two years, the fluctuation period dropped from 18 minutes to just 7 — the first-ever measurement of its kind around a supermassive black hole. If this represented an orbiting object, it was now moving at half the speed of light. Then something unexpected happened — the fluctuation period stabilized.
In this artist’s concept, matter is stripped from a white dwarf (sphere at lower right) orbiting within the innermost accretion disk surrounding 1ES 1927+654’s supermassive black hole. Astronomers developed this scenario to explain the evolution of rapid X-ray oscillations detected by ESA’s (European Space Agency) XMM-Newton satellite. ESA’s LISA (Laser Interferometer Space Antenna) mission, due to launch in the next decade, should be able to confirm the presence of an orbiting white dwarf by detecting the gravitational waves it produces. NASA/Aurore Simonnet, Sonoma State University “We were shocked by this at first,” Masterson explained. “But we realized that as the object moved closer to the black hole, its strong gravitational pull could begin to strip matter from the companion. This mass loss could offset the energy removed by gravitational waves, halting the companion’s inward motion.”
So what could this companion be? A small black hole would plunge straight in, and a normal star would quickly be torn apart by the tidal forces near the monster black hole. But the team found that a low-mass white dwarf — a stellar remnant about as large as Earth — could remain intact close to the black hole’s event horizon while shedding some of its matter. A paper led by Masterson summarizing these results will appear in the Feb. 13 edition of the journal Nature.
This model makes a key prediction, Masterson notes. If the black hole does have a white dwarf companion, the gravitational waves it produces will be detectable by LISA (Laser Interferometer Space Antenna), an ESA mission in partnership with NASA that is expected to launch in the next decade.
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
Artist concept highlighting the novel approach proposed by the 2025 NIAC awarded selection of Beholding Black Hole Power with the Accretion Explorer Interferometer concept.NASA/Kimberly Weaver Kimberly Weaver
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Some of the most enigmatic objects in the Universe are giant supermassive black holes (SMBH). Yet after 30 years of study, we don’t know precisely how these objects produce their power. This requires observations at X-ray wavelengths. The state-of-the-art for X-ray images is Chandra (~0.5-1 arcsecond resolution) but this is insufficient to image regions near SMBH where the most energetic behavior occurs. The Accretion Explorer (AE) is a mission architecture that will shatter new ground by creating X-ray images at scientifically crucial energies of 0.7-1.2 keV, 1.5-2.5 keV, 6-7 keV, up to 6 orders of magnitude better than Chandra, and will offer imaging at 4-5 orders of magnitude better than JWST (IR) and HST(optical/UV). The specific X-ray energy bands we are proposing to cover contain vital X-ray line signatures that can distinguish between SMBH activity and stellar processes. The AE NIAC concept would be a game changer for NASA and astrophysics. X-ray interferometry will challenge and change the conversation around future mission possibilities for NASA’s flagships. It will also influence the Astrophysics 2030 Decadal Survey and will significantly contribute to our scientific knowledge base in astrophysics and other fields. AE has tremendous potential to generate enthusiasm for future missions and the potential to build advocacy to support it within NASA, society, and the aerospace community.
Alternative approaches to ultra high-resolution X-ray imaging technology are not currently being funded. Our study will focus on a large free-flying X-ray interferometer. We will design a multiple spacecraft system that provides the architecture to align individual mirror pair baseline groupings provided by individual collector spacecraft, with the pointing precision to achieve micro-arcsecond resolution. Our study will assess the required pointing stability and determine optimal ways to nest and mount the collecting mirror flats within mirror modules. We will assess the required size for the detector array(s) to accommodate the wavelength coverage for detecting fringes, study how images will be created from fringes, and produce a simulated image from a design with accompanying optical element tolerance tables. We will document alternative approaches, how new factors substantially differentiate AE from prior efforts for X-ray interferometry, and identify technical hurdles.
As a result of performing this study, there are notable engineering benefits that can contribute to space missions, even if the concept is shown to be infeasible. These include establishing how small baseline interferometers can be flown with less risk in terms of spacing and tethering mirror modules, studies of very high levels of pointing precision for space-based interferometers, and extreme stability on target. Producing a simulated image from this design with accompanying tolerance tables can inform other space-based interferometry designs.
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NASA’s Dawn spacecraft captured this image of Vesta as it left the giant asteroid’s orbit in 2012. The framing camera was looking down at the north pole, which is in the middle of the image.NASA/JPL-Caltech/UCLA/MPS/DLR/IDA Known as flow formations, these channels could be etched on bodies that would seem inhospitable to liquid because they are exposed to the extreme vacuum conditions of space.
Pocked with craters, the surfaces of many celestial bodies in our solar system provide clear evidence of a 4.6-billion-year battering by meteoroids and other space debris. But on some worlds, including the giant asteroid Vesta that NASA’s Dawn mission explored, the surfaces also contain deep channels, or gullies, whose origins are not fully understood.
A prime hypothesis holds that they formed from dry debris flows driven by geophysical processes, such as meteoroid impacts, and changes in temperature due to Sun exposure. A recent NASA-funded study, however, provides some evidence that impacts on Vesta may have triggered a less-obvious geologic process: sudden and brief flows of water that carved gullies and deposited fans of sediment. By using lab equipment to mimic conditions on Vesta, the study, which appeared in Planetary Science Journal, detailed for the first time what the liquid could be made of and how long it would flow before freezing.
Although the existence of frozen brine deposits on Vesta is unconfirmed, scientists have previously hypothesized that meteoroid impacts could have exposed and melted ice that lay under the surface of worlds like Vesta. In that scenario, flows resulting from this process could have etched gullies and other surface features that resemble those on Earth.
To explore potential explanations for deep channels, or gullies, seen on Vesta, scientists used JPL’s Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE, to simulate conditions on the giant asteroid that would occur after meteoroids strike the surface.NASA/JPL-Caltech But how could airless worlds — celestial bodies without atmospheres and exposed to the intense vacuum of space — host liquids on the surface long enough for them to flow? Such a process would run contrary to the understanding that liquids quickly destabilize in a vacuum, changing to a gas when the pressure drops.
“Not only do impacts trigger a flow of liquid on the surface, the liquids are active long enough to create specific surface features,” said project leader and planetary scientist Jennifer Scully of NASA’s Jet Propulsion Laboratory in Southern California, where the experiments were conducted. “But for how long? Most liquids become unstable quickly on these airless bodies, where the vacuum of space is unyielding.”
The critical component turns out to be sodium chloride — table salt. The experiments found that in conditions like those on Vesta, pure water froze almost instantly, while briny liquids stayed fluid for at least an hour. “That’s long enough to form the flow-associated features identified on Vesta, which were estimated to require up to a half-hour,” said lead author Michael J. Poston of the Southwest Research Institute in San Antonio.
Launched in 2007, the Dawn spacecraft traveled to the main asteroid belt between Mars and Jupiter to orbit Vesta for 14 months and Ceres for almost four years. Before ending in 2018, the mission uncovered evidence that Ceres had been home to a subsurface reservoir of brine and may still be transferring brines from its interior to the surface. The recent research offers insights into processes on Ceres but focuses on Vesta, where ice and salts may produce briny liquid when heated by an impact, scientists said.
Re-creating Vesta
To re-create Vesta-like conditions that would occur after a meteoroid impact, the scientists relied on a test chamber at JPL called the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE. By rapidly reducing the air pressure surrounding samples of liquid, they mimicked the environment around fluid that comes to the surface. Exposed to vacuum conditions, pure water froze instantly. But salty fluids hung around longer, continuing to flow before freezing.
The brines they experimented with were a little over an inch (a few centimeters) deep; scientists concluded the flows on Vesta that are yards to tens of yards deep would take even longer to refreeze.
The researchers were also able to re-create the “lids” of frozen material thought to form on brines. Essentially a frozen top layer, the lids stabilize the liquid beneath them, protecting it from being exposed to the vacuum of space — or, in this case the vacuum of the DUSTIE chamber — and helping the liquid flow longer before freezing again.
This phenomenon is similar to how on Earth lava flows farther in lava tubes than when exposed to cool surface temperatures. It also matches up with modeling research conducted around potential mud volcanoes on Mars and volcanoes that may have spewed icy material from volcanoes on Jupiter’s moon Europa.
“Our results contribute to a growing body of work that uses lab experiments to understand how long liquids last on a variety of worlds,” Scully said.
Find more information about NASA’s Dawn mission here:
https://science.nasa.gov/mission/dawn/
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