It started as a routine data-quality check. But as Robert Wagner, a scientist with NASA’s Lunar Reconnaissance Orbiter (LRO), scanned a giant Moon map on his computer screen, an unusually large bright spot circled by a dark halo caught his eye, as it implied that surface material in that area had been shaken up.

“I just stopped, dropped everything, and started looking into what that spot was,” said Wagner, an image-processing specialist from Intuitive Machines who works with data from the Lunar Reconnaissance Orbiter Camera (LROC) system.

By comparing before and after images of the Moon, Wagner realized he had discovered the largest, newly formed crater ever found in the solar system, as scientists reported Wednesday in Science Advances. This discovery highlights the value of NASA’s Moon orbiter data in studying a dynamic landscape as the agency advances a sustained human presence and expanded scientific and commercial activity on the Moon.

Officially named McGetchin after pioneering lunar scientist Tom McGetchin, the crater formed on the Moon’s eastern edge sometime between April 11 and May 22, 2024, after a comet or asteroid the size of a three- to six-story building hit the surface.
 
The crash left a crater, 728 feet wide, that spans the length of two football fields. And at 141 feet deep, the crater could fit three vertically stacked yellow school buses.
 
Scientists estimate that an impact of this magnitude happens on the Moon about once in a century or even longer.

Moon takes some hits

For more than 17 years, LRO has been circling the Moon and using its seven instruments to map the topography, surface composition, temperature, and radiation environment there. The spacecraft’s team has identified at least 1,000 new impact craters throughout the mission and flagged 100,000 more surface changes from an object smashing into the Moon or from the debris that flung out after.

With no atmosphere to slow them or burn them up, space rocks and other objects easily reach the lunar surface. Most are much smaller compared to the object that carved out McGetchin crater. The smallest craters scientists can distinguish from LRO images are about 30 feet wide, the length of a three-story building laid on its side, made by rocks about 43 inches wide, the size of a monster-truck tire. Scientists estimate that impacts of this scale produce about 140 new craters across the Moon each year. But most new ones are made by microscopic projectiles that leave holes too small to identify in orbital images.

With its numerous instruments, the spacecraft can observe changes to the lunar surface that aren’t apparent in the LROC images alone. After the crater was discovered, scientists working with LRO’s thermal instrument, Diviner, made follow-up observations of the site. They found a 4-mile-wide area around the crater that is about 16 degrees Fahrenheit cooler at night than its surroundings.

Reporting in a second paper Wednesday in the same journal, researchers say that the cooling happens because the impact fluffs up the regolith around the crater, making it less dense and therefore less able to retain heat.

The large extent of this “cold spot” is striking, scientists say, because it shows that impacts can modify the Moon’s surface far beyond the crater itself. These physical changes could affect how rover wheels interact with the surface, for instance.

Road to discovery

The LROC system collects images from about 60 miles above the Moon as LRO loops from pole to pole. The system includes two cameras that capture high‑resolution black‑and‑white images and one camera for moderate‑resolution multispectral images. Over the years and thousands of passes, scientists have built maps detailed enough to spot not only new craters, but also landslides, landers, seismic faults, and even hints of lava tubes.

LROC scientists regularly analyze close-up images of small portions of the Moon’s surface taken by the Narrow-Angle Camera. Using these images, they look for changes that are typically less than 30 feet across. But every few years the team searches for large (wider than 150 feet) features by creating global Moon maps and comparing them to older versions.

That’s what Wagner was doing on Oct. 24, 2025, when he came across McGetchin. Using images from LROC’s Wide-Angle Camera, which captures broad views with pixels the size of football fields, he stacked hundreds of “before” and “after” frames with software designed to highlight change. Anything that stayed the same turned gray while anything different showed up as bright or dark patches.

While the process sounds straightforward, spotting real craters requires a lot of manual work. The software flags every tiny shift in lighting or shadow, generating hundreds of false alarms. For this reason, Wagner typically verifies the software, looking for small fuzzy halos around pixel‑wide bright points, which indicate splashes of regolith around a new crater.

Spanning hundreds of pixels, McGetchin stood out immediately. “It was by far the most obvious impact debris pattern I’ve ever seen in one of these images,” Wagner said.

After his discovery, scientists turned to the Narrow-Angle Camera, which takes much sharper views at about 3 feet per pixel. This camera’s close-up images, taken as LRO flew over the impact site again, revealed the crater size, shape, and how the surrounding terrain was affected. These images also helped researchers estimate the size and force of the rock fragment that formed the new crater, details that are expected to appear in a future paper.

Banner image caption: A zoomed-in view of the Moon, with debris around McGetchin crater visible as a white spot circled by a dark halo just right of center of the image (marked with black arrows). This is the view that Robert Wagner saw on Oct. 24, 2025, during a routine data-quality check. Wagner is an image processing specialist for NASA’s Lunar Reconnaissance Orbiter Camera, a system of three cameras. Using images from the Wide-Angle Camera (WAC), which captures broad views with pixels the size of American football fields, he stacked hundreds of images captured by WAC over the last several years with software designed to highlight change. Anything that stayed the same is gray; anything that changed showed up as bright or dark patches. The stripes in the image are due to slight changes in lighting between the older and newer images. This image composite shows an area of the Moon approximately 900 miles across.

The post NASA’s Moon Orbiter Spots New, ‘Once-in-Century’ Moon Crater appeared first on NASA Science.

It started as a routine data-quality check. But as Robert Wagner, a scientist with NASA’s Lunar Reconnaissance Orbiter (LRO), scanned a giant Moon map on his computer screen, an unusually large bright spot circled by a dark halo caught his eye, as it implied that surface material in that area had been shaken up.

“I just stopped, dropped everything, and started looking into what that spot was,” said Wagner, an image-processing specialist from Intuitive Machines who works with data from the Lunar Reconnaissance Orbiter Camera (LROC) system.

By comparing before and after images of the Moon, Wagner realized he had discovered the largest, newly formed crater ever found in the solar system, as scientists reported Wednesday in Science Advances. This discovery highlights the value of NASA’s Moon orbiter data in studying a dynamic landscape as the agency advances a sustained human presence and expanded scientific and commercial activity on the Moon.

Officially named McGetchin after pioneering lunar scientist Tom McGetchin, the crater formed on the Moon’s eastern edge sometime between April 11 and May 22, 2024, after a comet or asteroid the size of a three- to six-story building hit the surface.
 
The crash left a crater, 728 feet wide, that spans the length of two football fields. And at 141 feet deep, the crater could fit three vertically stacked yellow school buses.
 
Scientists estimate that an impact of this magnitude happens on the Moon about once in a century or even longer.

Moon takes some hits

For more than 17 years, LRO has been circling the Moon and using its seven instruments to map the topography, surface composition, temperature, and radiation environment there. The spacecraft’s team has identified at least 1,000 new impact craters throughout the mission and flagged 100,000 more surface changes from an object smashing into the Moon or from the debris that flung out after.

With no atmosphere to slow them or burn them up, space rocks and other objects easily reach the lunar surface. Most are much smaller compared to the object that carved out McGetchin crater. The smallest craters scientists can distinguish from LRO images are about 30 feet wide, the length of a three-story building laid on its side, made by rocks about 43 inches wide, the size of a monster-truck tire. Scientists estimate that impacts of this scale produce about 140 new craters across the Moon each year. But most new ones are made by microscopic projectiles that leave holes too small to identify in orbital images.

With its numerous instruments, the spacecraft can observe changes to the lunar surface that aren’t apparent in the LROC images alone. After the crater was discovered, scientists working with LRO’s thermal instrument, Diviner, made follow-up observations of the site. They found a 4-mile-wide area around the crater that is about 16 degrees Fahrenheit cooler at night than its surroundings.

Reporting in a second paper Wednesday in the same journal, researchers say that the cooling happens because the impact fluffs up the regolith around the crater, making it less dense and therefore less able to retain heat.

The large extent of this “cold spot” is striking, scientists say, because it shows that impacts can modify the Moon’s surface far beyond the crater itself. These physical changes could affect how rover wheels interact with the surface, for instance.

Road to discovery

The LROC system collects images from about 60 miles above the Moon as LRO loops from pole to pole. The system includes two cameras that capture high‑resolution black‑and‑white images and one camera for moderate‑resolution multispectral images. Over the years and thousands of passes, scientists have built maps detailed enough to spot not only new craters, but also landslides, landers, seismic faults, and even hints of lava tubes.

LROC scientists regularly analyze close-up images of small portions of the Moon’s surface taken by the Narrow-Angle Camera. Using these images, they look for changes that are typically less than 30 feet across. But every few years the team searches for large (wider than 150 feet) features by creating global Moon maps and comparing them to older versions.

That’s what Wagner was doing on Oct. 24, 2025, when he came across McGetchin. Using images from LROC’s Wide-Angle Camera, which captures broad views with pixels the size of football fields, he stacked hundreds of “before” and “after” frames with software designed to highlight change. Anything that stayed the same turned gray while anything different showed up as bright or dark patches.

While the process sounds straightforward, spotting real craters requires a lot of manual work. The software flags every tiny shift in lighting or shadow, generating hundreds of false alarms. For this reason, Wagner typically verifies the software, looking for small fuzzy halos around pixel‑wide bright points, which indicate splashes of regolith around a new crater.

Spanning hundreds of pixels, McGetchin stood out immediately. “It was by far the most obvious impact debris pattern I’ve ever seen in one of these images,” Wagner said.

After his discovery, scientists turned to the Narrow-Angle Camera, which takes much sharper views at about 3 feet per pixel. This camera’s close-up images, taken as LRO flew over the impact site again, revealed the crater size, shape, and how the surrounding terrain was affected. These images also helped researchers estimate the size and force of the rock fragment that formed the new crater, details that are expected to appear in a future paper.

Banner image caption: A zoomed-in view of the Moon, with debris around McGetchin crater visible as a white spot circled by a dark halo just right of center of the image (marked with black arrows). This is the view that Robert Wagner saw on Oct. 24, 2025, during a routine data-quality check. Wagner is an image processing specialist for NASA’s Lunar Reconnaissance Orbiter Camera, a system of three cameras. Using images from the Wide-Angle Camera (WAC), which captures broad views with pixels the size of American football fields, he stacked hundreds of images captured by WAC over the last several years with software designed to highlight change. Anything that stayed the same is gray; anything that changed showed up as bright or dark patches. The stripes in the image are due to slight changes in lighting between the older and newer images. This image composite shows an area of the Moon approximately 900 miles across.

University of Bern simulations and ESA Hera observations point to one non-destructive asteroid impact as the source of Deimos’ southern depression and dusty surface.

The post A Single Asteroid Impact May Have Shaped Mars’ Moon Deimos appeared first on Curiosmos.

The technology is far from the only existential risk our species faces. But weighing such cosmic fears can become a mind-bending exercise.

On Sept. 8, 2016, the Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer (OSIRIS-REx) mission launched from Cape Canaveral, setting off on its 4.4-billion-mile (2 billion kilometers) journey to asteroid Bennu. About the size of an SUV, the OSIRIS-REx spacecraft carries several cameras, an altimeter used to create maps of Bennu, and anContinue reading "Sept. 8, 2016: OSIRIS-REx launches"

The post Sept. 8, 2016: OSIRIS-REx launches appeared first on Astronomy Magazine.

The Perseids will be most active on Wednesday into Thursday morning, on the moonless night after a total solar eclipse.

For nearly three decades, 1998 SH2 looked like a fairly ordinary near-Earth asteroid. It was discovered in 1998, catalogued, and followed through a 4½-year orbit around the Sun. Then, during a close but safe pass by Earth in August 2025, its motion refused to match the path astronomers had calculated. The explanation, announced by NASA […]

The post A Near-Earth Object Called an Asteroid for Decades Turns Out to Be a Comet appeared first on Curiosmos.

Only one white dwarf star has ever been caught eating an asteroid. Recently, however, astronomers may have found another that just finished its meal.

Eating Asteroids

Although stars like our Sun don’t explode in violent supernovae like their massive counterparts, they don’t slink quietly into a peaceful old age either. When a solar-mass star reaches the end of its main sequence life, it first swells dramatically (the Sun may eventually grow so large that it consumes Earth and the device you’re reading this on), then shrinks down to a tiny but incredibly hot ember known as a white dwarf.

As one might imagine, this process is not kind to any planets or asteroids that were previously circling the star. While some might survive, others are sent spiraling inwards where they break apart and are accreted onto their hosts. Due to the extreme temperatures and surface gravity of white dwarfs, whatever falls on their surfaces is vaporized, sorted by weight, and quickly dragged out of sight. Since heavy elements cannot last long in a white dwarf’s atmosphere, whenever astronomers see their stains in the star’s spectrum, they know that the star must have recently consumed the rocky remains of their former asteroids and planets.

However, although researchers have found these stains in over a quarter of white dwarfs and consequently have reasoned that asteroid snacking must be common, they’ve only ever caught one star mid-meal. Recently, Ben Zuckerman (University of California, Los Angeles) and a team of collaborators may have found another, though it may have just finished dining.

Leftover Crumbs

This new star, called WD J0234-0406, shares some characteristics with the “iconic” WD 1145+017 that was first spotted mid-meal, but it also differs in an interesting way. High-resolution spectroscopy reveals that both stars have gaseous material orbiting around them along highly non-circular paths. These have been interpreted as “precessing rings of high velocity gas” that previously belonged to parent asteroids. However, while WD 1145+017 appears to flicker as bits of disintegrating asteroids pass between it and our line of sight, WD J0234-0406 is rock steady. Neither TESS nor the Zwicky Transient Facility have detected any dips in light from the star despite the evidence that solid material must have recently drizzled into the star’s atmosphere.

The researchers suggest that this relative quiet is a matter of timing. While asteroids are actively breaking up around WD 1145+017, the parent bodies that supplied the gas and dust around WD J0234-0406 may have shattered long ago and have already been either vaporized or ground down into smaller particles. All that is left over are the crumbs slowly spiraling toward the star.

Although WD J0234-0406’s meal may not be as dramatic as WD 1145+017’s feast, it’s still exciting to expand the sample of known white dwarf-asteroid interactions. And, with the upcoming release of data from the DESI survey poised to reveal the spectra of tens of thousands of white dwarfs, the sample is likely to grow again soon.

Citation

“High-velocity Circumstellar Gas Orbiting a White Dwarf Star,” B. Zuckerman et al 2026 ApJ 1004 254. doi:10.3847/1538-4357/ae23c4

The post Finishing Off an Asteroid appeared first on AAS Nova.

The end of July brings the Alpha Capricornids and the Southern Delta Aquarids, both of which will be most active on Thursday night into Friday morning.

Some 66 million years ago, an asteroid impact wiped out three-quarters of all plant and animal species on Earth, most notably taking down the dinosaurs. But exactly how that impact caused those extinctions has been the subject of fierce debate. According to a new paper published in the Journal of Geophysical Research: Biogeosciences, the impact would have produced an immense cloud of dust that superheated the upper atmosphere, charbroiling living organisms unable to take shelter and igniting widespread wildfires.

As previously reported, the most widely accepted explanation for what triggered that catastrophic mass extinction is known as the “Alvarez hypothesis,” after the late physicist Luis Alvarez and his geologist son, Walter. In 1980, they proposed that the extinction event may have been caused by a massive asteroid or comet hitting the Earth. They based this conclusion on their analysis of sedimentary layers at the Cretaceous-Paleogene boundary(the K-Pg boundary, formerly known as the K-T boundary) found all over the world, which included unusually high concentrations of iridium—a metal more commonly found in asteroids than on Earth. (That same year, Dutch geophysicist Jan Smit independently arrived at a similar conclusion.)

Since then, scientists have identified a likely impact site: a large crater in Chicxulub, Mexico, in the Yucatan Peninsula, first discovered by geophysicists in the late 1970s. The impactor that created it was sufficiently large (between 11 and 81 kilometers, or 7 to 50 miles) to melt, shock, and eject granite from deep inside the Earth, probably causing a megatsunami and ejecting vaporized rock and sulfates into the atmosphere. It has been estimated that the impact would have released energy over a billion times higher than the atomic bombs dropped on Hiroshima and Nagasaki in 1945.

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The Hoba meteorite smashed into the Earth, but look around it, and you won't see any crater.

When NASA’s OSIRIS-REx spacecraft delivered pristine samples from the asteroid Bennu back to Earth in 2023, scientists knew they were receiving one of the most chemically untouched collections of material ever recovered from the Solar System.

Since then, the returned grains have steadily transformed researchers’ understanding of how asteroids formed, how water altered primitive worlds, and even how the ingredients for life may have spread through the early Solar System.

Now, a new study, published in Nature Communications, has uncovered another surprise hidden inside those microscopic particles. Embedded within Bennu are tiny mineral fragments that formed during the Solar System’s earliest moments—less than 100,000 years after its birth—and they may reveal that the asteroid’s ancient parent body formed much farther from the Sun than scientists once suspected.

The research suggests that Bennu inherited some of the oldest surviving solids ever created, while simultaneously preserving evidence that Jupiter’s formation may have acted as an enormous cosmic filter, separating different populations of dust before planets had even fully formed.

“Our observations of phyllosilicates replacing olivine and interstitial phyllosilicates between olivine grains within AOAs… collectively indicate that these refractory inclusions experienced aqueous alteration on Bennu’s parent planetesimal,” researchers write. “Therefore, they were incorporated into the parent planetesimal before the onset of aqueous alteration, during which phyllosilicates and magnetite formed.”

“These mineralogical, isotopic, and chronological similarities among refractory inclusions in Bennu samples, Ryugu samples, and CI chondrites provide evidence that their parent planetesimal(s) accreted a common suite, and likely similar relative abundances, of high-temperature refractory inclusions and their fragments,” researchers write.

The research concentrates on “refractory inclusions”—tiny mineral-rich objects known as calcium-aluminum-rich inclusions (CAIs) and amoeboid olivine aggregates (AOAs). These objects are widely considered the oldest solid materials to condense from the hot gas surrounding the newborn Sun.

Long before planets existed, the infant Solar System consisted of a rotating disk of gas coupled with dust known as the protoplanetary disk. Temperatures near the young Sun exceeded 2,000 degrees Fahrenheit (roughly 1,100 degrees Celsius), allowing only the most heat-resistant minerals to crystallize.

These refractory inclusions were among the very first solids to emerge from that environment before eventually being transported throughout the growing Solar System.

Although scientists have found such inclusions in meteorites for decades, Bennu offered an unprecedented opportunity to examine them in material collected directly from an asteroid rather than from meteorites that survived passage through Earth’s atmosphere.

To investigate, researchers analyzed polished sections prepared from 12 Bennu particles using scanning electron microscopy, transmission electron microscopy, oxygen isotope measurements, and radioactive aluminum-magnesium dating techniques.

The team identified six amoeboid olivine aggregates and three calcium-aluminum-rich inclusions, all remarkably small—none exceeding roughly 100 micrometers across, or about the thickness of a human hair. This turned out to be one of the study’s most important discoveries.

The mineral chemistry and oxygen isotopes showed these inclusions formed in an extremely hot, oxygen-16-rich environment during the Solar System’s earliest stages. Radioactive dating using aluminum-26 indicated at least one inclusion formed essentially at the very beginning of Solar System history, within roughly the first 100,000 years after the earliest known solids condensed.

In other words, Bennu contains fragments that have survived for approximately 4.567 billion years with surprisingly little alteration. Yet, those ancient relics also preserve evidence that they later encountered liquid water.

Several inclusions show minerals partially replaced by phyllosilicates—water-bearing clay minerals—while magnetite and other alteration products reveal that water once circulated through Bennu’s ancient parent body after these primordial objects had already become incorporated into it.

For scientists, that sequence helps establish a timeline. First, the earliest high-temperature solids formed close to the newborn Sun. Later, they were transported outward through the protoplanetary disk. Only after they became part of Bennu’s larger parent asteroid did liquid water alter portions of the rock.

Researchers found distinct similarities between Bennu’s inclusions and those previously identified in samples returned from Japan’s Hayabusa2 mission to asteroid Ryugu, as well as in rare CI carbonaceous chondrite meteorites found on Earth.

The oxygen isotopes, crystal chemistry, and formation ages all closely match, suggesting these seemingly distant objects inherited material from the same population of ancient Solar System building blocks.

That mutual heritage points toward a surprisingly interconnected early Solar System, where material formed close to the Sun was efficiently transported across enormous distances before eventually becoming incorporated into multiple asteroid populations.

However,  the absence of something proved just as revealing as what scientists found.

Unlike many carbonaceous meteorites, Bennu contains no large refractory inclusions larger than about one-tenth of a millimeter. Other meteorites frequently preserve inclusions ranging from submillimeter sizes up to several centimeters across.

According to the researchers, the missing population may reflect the increasing influence of the Solar System’s first giant planet.

As proto-Jupiter accumulated mass, its gravity likely created a pressure bump within the gas disk encircling the young Sun. Such pressure bumps act as natural traffic jams for dust, trapping larger particles while allowing much smaller grains to continue drifting through the disk.

Under this scenario, larger refractory inclusions became concentrated closer to Jupiter’s orbit. At the same time, only the smallest particles were able to migrate farther outward into the distant regions where Bennu’s parent body eventually formed.

If correct, Bennu’s microscopic inclusions effectively record the influence of Jupiter before the giant planet had even fully matured.

The hypothesis also helps explain why Bennu, Ryugu, and CI meteorites all possess nearly identical populations of tiny refractory inclusions while lacking the larger varieties commonly found elsewhere.

Rather than showing different source materials, the distinction may instead reflect where—and perhaps when—their parent bodies assembled within the developing protoplanetary disk.

The findings similarly reinforce earlier studies suggesting Bennu is among the Solar System’s most chemically primitive objects. Because large refractory inclusions contain unusually high concentrations of certain elements, their absence helps preserve Bennu’s overall composition close to that of the earliest solar nebula from which the planets formed.

That makes the asteroid an unusually valuable time capsule. Every new microscopic grain examined inside the OSIRIS-REx collection provides another insight into processes that occurred billions of years before Earth existed as a habitable world.

Rather than simply representing rubble from a small asteroid, Bennu appears to preserve a remarkably faithful record of how the Solar System sorted, mixed, transported, and assembled its earliest building materials.

The study also demonstrates why sample-return missions have grown increasingly important to planetary science. Laboratory instruments on Earth can perform measurements impossible for spacecraft operating millions of miles away, letting researchers reconstruct events that occurred within the Solar System’s first fractions of a million years.

“We conclude that Bennu’s parent planetesimal, like those of Ryugu and CI chondrites, accreted small refractory inclusions that persisted in the outer Solar System beyond the influence of the proto-Jupiter-induced pressure bump,” researchers write. “Taken together, these findings highlight the need to integrate Bennu samples into comparative studies of early Solar System solids to better constrain the diversity and possible genetic links among planetesimal formation pathways,” researchers write.

The study, “Refractory inclusions in Bennu samples indicative of outer Solar System accretion,” appeared in Nature Communications.

Tim McMillan is a retired law enforcement executive, investigative reporter and co-founder of The Debrief. His writing typically focuses on defense, national security, the Intelligence Community and topics related to psychology. You can follow Tim on Twitter: @LtTimMcMillan.  Tim can be reached by email: tim@thedebrief.org or through encrypted email: LtTimMcMillan@protonmail.com 

A meteorite recovered immediately upon its fall to Earth on July 16, 2024, is helping NASA scientists uncover new clues about ancient water, the chemical evolution of primitive asteroids, and the ingredients that may have helped make life possible throughout the early solar system.

This rapid recovery began when an amateur astronomer in New Jersey quickly recognized that a newly fallen meteorite had landed on his property. Recognizing its scientific value and wearing protective gloves, he collected the fragments and stored them in aluminum foil and glass containers, which preserved delicate minerals and organic compounds that are often altered by moisture, weather, and contamination.

As the meteorite fell to Earth, cameras across New Jersey captured its fiery passage through the atmosphere. Scientists used these observations to reconstruct the fireball’s trajectory and, after recovering the meteorite, combined this data with laboratory analyses to determine where in the solar system the rock most likely originated. In a study published Wednesday in the journal Science Advances, researchers found evidence that ancient salty water altered minerals within the meteorite’s parent asteroid, preserving unique minerals and a rich inventory of organic compounds.

“When we have both a documented fireball and a quick recovery of its meteorite, we can learn not only what the rock is made of, but where it came from in the asteroid belt,” said Peter Jenniskens, meteor astronomer at both NASA’s Ames Research Center in California’s Silicon Valley and the SETI Institute, and lead author of the study.

Named for the township where it was recovered, the Hillsborough meteorite belongs to a class of carbon-rich meteorites known as CM carbonaceous chondrites. These primitive rocks preserve some of the oldest materials in the solar system, recording the chemical processes that shaped asteroids more than 4.5 billion years ago.

While examining the unusually pristine meteorite, researchers found a mosaic of tiny broken-up rocks and noticed that some contained unusually high concentrations of sodium — an unexpected finding for this type of meteorite. The surprising signal prompted a closer investigation using powerful electron microscopes that allowed scientists to examine the meteorite from the millimeter scale down to individual atoms. By combining observations across multiple scales, researchers reconstructed the history of the minerals and the fluids that once flowed through them.

These analyses revealed microscopic fractures filled with sodium-rich material left behind by ancient brines. Unlike pure water, brines contain dissolved salts that allow them to transport elements and chemically alter the rocks they move through. In the case of the Hillsborough sample, those ancient fluids altered the asteroid’s minerals and left behind chemical evidence that remained preserved for billions of years.

Scientists were also able to detect fragile sodium-carbonate salts that normally react with moisture in Earth’s atmosphere before they can be studied. Jangmi Han, a paper co-author and mineralogist at NASA’s Johnson Space Center in Houston, identified evidence of ancient brines preserved within microscopic fractures. Similar salts were identified in samples returned from the asteroids Bennu and Ryugu by NASA’s OSIRIS-REx mission and JAXA’s (Japan Aerospace Exploration Agency) Hayabusa2 mission. However,Hillsborough marks the first time the salts have been identified in a CM carbonaceous chondrite meteorite, offering a new glimpse into the surfaces of the primitive asteroids that produced these meteorites.

Together, these findings suggest that ancient, salt-rich brines were more widespread among primitive asteroids than previously recognized, and provide scientists with new opportunities to compare how water altered different asteroid bodies across the early solar system.

“The chips of the most salt-rich bits of this meteorite are quite comparable to the samples returned by the Hayabusa2 and OSIRIS-REx missions,” said Mike Zolensky, a meteorite researcher at NASA Johnson and co-author of the study. “They’re not identical. They’re different in some very interesting ways, but they’ve seen very similar processes.”

Scientists expected Hillsborough to contain a rich suite of organic compounds because it is a CM carbonaceous chondrite. What made the meteorite exceptional was how quickly it was recovered, allowing researchers to study those compounds before prolonged exposure to Earth’s environment could contaminate the sample.

“One of the big surprises for me when we analyzed a small chip of the Hillsborough meteorite was the complexity of amino acids and other organic compounds,” said Danny Glavin, senior scientist in the Astrobiology Analytical Laboratory at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and co-author of the study.

Its diversity of amino acids and other organic compounds is, comparable to the Murchison meteorite, a nearly 100-kilogram carbonaceous chondrite that fell in Australia in 1969 and became the benchmark for extraterrestrial organic chemistry.

“It’s just more proof that the chemical building blocks of life could have been delivered — and are still being delivered — to Earth today by these carbonaceous asteroid fragments,” said Glavin, who was a co-investigator on OSIRIS-REx, leading an international team that studied the organic composition of the samples delivered to Earth from asteroid Bennu in 2023.

Understanding the Hillsborough meteorite required expertise from multiple scientific disciplines.

Astronomers reconstructed the meteorite’s journey through space, finding evidence that it may have originated from the Erigone asteroid family in the inner asteroid belt, home to the asteroid Donaldjohanson, which was visited in 2025 by NASA’s Lucy spacecraft. Mineralogists identified evidence of ancient brines preserved within microscopic fractures, while organic chemists analyzed the meteorite’s inventory of amino acids and other organic compounds.

“Together, those complementary studies are helping scientists build one of the clearest pictures yet of how primitive asteroids such as the asteroid Erigone evolved chemically over billions of years,” said Jenniskens.

Researchers continue to study the Hillsborough meteorite, revealing new details about how water transformed primitive asteroids and shaped the early solar system.

By tracing the history of water on primitive asteroids, scientists are learning how water and the chemical ingredients for life were distributed throughout the early solar system.

“If you follow the water through the solar system, you’re actually following life,” Zolensky said. “Following the history of water through the solar system is an essential part of understanding the origin of life.”

For more information on NASA’s astromaterials research and exploration, visit:

https://science.nasa.gov/astromaterials

Karen Fox / Molly Wasser
Headquarters, Washington
240-285-5155 / 240-419-1732
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

Victoria Segovia
NASA’s Johnson Space Center, Houston 281-483-5111
victoria.segovia@nasa.gov

A New Jersey couple helped scientists uncover the makeup of an unusual asteroid after it fell into their bedroom.

NASA’s Perseverance Mars rover has uncovered evidence that a 245-foot-thick (75-meter-thick) stack of ancient rock on the rim of Jezero Crater was built by repeated asteroid impacts. Referred to as the “Broom Point member” by the rover’s science team, this sequence of layered bedrock is likely more than 3.9 billion years old, making it among the oldest terrain ever examined by a Mars rover.  

Released Wednesday in the Journal of Geophysical Research: Planets, the findings offer a window into one of the most tumultuous chapters in the history of the solar system.  

“Since leaving Jezero, Perseverance has been exploring a brand-new frontier, both geographically and geologically — a chapter of Martian time that predates the crater itself,” said Ken Farley, Perseverance deputy project scientist at Caltech in Pasadena, California. “On Earth, our earliest geologic history has been fundamentally broken up, deformed, and erased by plate tectonics. Because Mars lacks plate tectonics to recycle its crust, this ancient record remains intact, giving us a rare glimpse into a geological time period that doesn’t exist on our own planet.” 

Reading between layers 

After ascending the western rim of Jezero Crater in late 2024, Perseverance began examining surrounding locations with its science instruments. Their data at Broom Point revealed six distinct rock types, including breccias — rocks composed of angular fragments — alternating with layers of fine-grained, pulverized rock dust. Rock fragments within the breccias are pocked with gas-bubble cavities, indicating they were once molten. 

The presence of tiny, dark, glassy beads within the layers offered an important clue about how these rocks formed. While volcanoes can produce similar glassy droplets, they rarely occur in such high abundance, pointing to asteroid impacts, instead, as the primary architect. In fact, the largest beads rival those flung out by the dinosaur-killing Chicxulub asteroid’s impact on Earth. 

The repetition of these distinct rock types multiple times throughout this thick sequence of rock indicates that high-energy impact events happened again and again across this region of early Mars. 

“The different rock layers are a record of variable-sized impacts occurring at different distances from where this rock sequence was accumulating,” said Alex Jones, a Ph.D. student in planetary geology at Imperial College London and lead author of the paper. “Some large impacts took place very far away, some small impacts nearby. Their debris all ended up landing here, constructing this thick section of rock.”  

How these layers formed may suggest an interaction with water or ice. Several of the layers look like they may have been formed by fast, ground-hugging debris flows. On Earth, these powerful, fluidlike surges can occur when molten rock hits water or ice that instantly flashes into steam.  

Cosmic one-two punch 

Some of Broom Point’s layers tilt at angles exceeding 80 degrees — nearly vertical — which is far too steep to be caused by the impact that created Jezero Crater.  

Instead, scientists suspect a cosmic “one-two punch” shaped this landscape long ago. First, a colossal asteroid impact created the 1,200-mile-wide (1,900-kilometer-wide) Isidis Basin, one of the largest impact basins on Mars, upending and tilting the once-flat rock layers. Later, a second asteroid likely struck, forming Jezero Crater, which measures 28 miles (45 kilometers) across. This second impact fractured and uplifted the already-tilted rocks into the dramatic formations the rover sees today.  

To pin down exactly when these events took place, the Perseverance team collected two core samples, dubbed “Bell Island” and “Main River.” If a future mission were to return them to Earth, laboratory dating could determine when and how often impacts were occurring on early Mars — and, by extension, the infant Earth, whose own early impact record has been erased by billions of years of plate tectonics. 

“During this violent era, it wasn’t rain or snow falling from the sky, but an almost constant barrage of molten rock droplets and pulverized dust kicked up by asteroid impacts,” said Jones. “If we can pin down the ages of these layers, it would be like reading a cosmic weather report from 4 billion years ago.” 

More about Perseverance 

NASA’s Jet Propulsion Laboratory in Southern California, which is managed for the agency by Caltech, built and manages operations of the Perseverance rover on behalf of the agency’s Science Mission Directorate in Washington, as part of NASA’s Mars Exploration Program portfolio. Arizona State University leads the operations of the rover’s Mastcam-Z instrument, working in collaboration with Malin Space Science Systems in San Diego, on the design, fabrication, testing, and operation of the cameras. SuperCam is led by Los Alamos National Laboratory in New Mexico, where the instrument’s Body Unit was developed. The rover’s SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals) instrument was built at NASA JPL, and its WATSON (Wide Angle Topographic Sensor for Operations and eNgineering) camera was built at Malin Space Science Systems.

For more information on NASA’s Perseverance, visit:

https://science.nasa.gov/mission/mars-2020-perseverance

News Media Contacts

DC Agle 
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov  

Karen Fox / Alana Johnson
NASA Headquarters, Washington
240-285-5155 / 202-672-4780
karen.c.fox@nasa.gov / alana.r.johnson@nasa.gov

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