Mercury's 'missing' meteorites may have finally been found on Earth
Most meteorites that have reached Earth come from the asteroid belt between Mars and Jupiter. But we have 1,000 or so meteorites that come from the Moon and Mars. This is probably a result of asteroids hitting their surfaces and ejecting material towards our planet.
It should also be physically possible for such debris to reach the Earth from Mercury, another nearby rocky body. But so far, none have been confirmed to come from there — presenting a longstanding mystery.
A new study my colleagues and I conducted has discovered two meteorites that could have a Mercurian origin. If confirmed, they would offer a rare window into Mercury's formation and evolution, potentially reshaping our understanding of the planet nearest the Sun.
Because Mercury is so close to the Sun, any space mission to retrieve a sample from there would be complex and costly. A naturally delivered fragment, therefore, may be the only practical way to study its surface directly — making such a discovery scientifically invaluable.
Observations from NASA's Messenger mission have inferred the surface composition of Mercury. This suggests the presence of minerals known as such as sodium-rich plagioclase (such as albite), iron-poor pyroxene (for example enstatite), iron-poor olivine (such as forsterite) and sulfide minerals such as oldhamite.
The meteorite Northwest Africa (NWA) 7325 was initially proposed as a possible fragment of Mercury. However, its mineralogy includes chromium-rich pyroxene containing approximately 1% iron. This poorly matches Mercury's estimated surface composition. As a result of this, and other factors, this link has been challenged.
Related: Mercury may have a 'potentially habitable' region below its surface, salty glaciers suggest
Aubrite meteorites have also been proposed as potential Mercurian fragments. Recent modeling of their formation suggests an origin from a large planetary body approximately 5,000km in diameter (similar to Mercury), potentially supporting this hypothesis.
Although aubrites do not exhibit chemical or spectral (the study of how light is broken up by wavelength) similarities with Mercury's surface, it has been hypothesized that they may derive from the planet's shallow mantle (the layer beneath the surface). Despite ongoing research, the existence of a definitive meteorite from Mercury remains unproven.
Our latest study investigated the properties of two unusual meteorites, Ksar Ghilane 022 and Northwest Africa 15915. We found that the two samples appear to be related, probably originating from the same parent body. Their mineralogy and surface composition also exhibit intriguing similarities to Mercury's crust. So this has prompted us to speculate about a possible Mercurian origin.
Both meteorites contain olivine and pyroxene, minor albitic plagioclase and oldhamite. Such features are consistent with predictions for Mercury's surface composition. Additionally, their oxygen compositions match those of aubrites. These shared characteristics make the samples compelling candidates for being Mercurian material.
However, notable differences exist. Both meteorites contain only trace amounts of plagioclase, in contrast to Mercury's surface, which is estimated to contain over 37%. Furthermore, our study suggests that the age of the samples is about 4,528 million years old. This is significantly older than Mercury's oldest recognised surface units, which are predicted (based on crater counting) to be approximately 4,000 million years.
If these meteorites do originate from Mercury, they may represent early material that is no longer preserved in the planet's current surface geology.
To link any meteorite to a specific asteroid type, moon or planet is extremely challenging. For example, laboratory analysis of Apollo samples allowed meteorites found in desert collection expeditions to be matched with the lunar materials. Martian meteorites have been identified through similarities between the composition of gases trapped in the meteorites with measurements of the martian atmosphere by spacecraft.
Until we visit Mercury and bring back material, it will be extremely difficult to assess a meteorite-planet link.
The BepiColombo space mission, by the European and Japanese space agencies, is now in orbit around Mercury and is about to send back high-resolution data. This may help us determine the ultimate origin body for Ksar Ghilane 022 and Northwest Africa 15915.
If meteorites from Mercury were discovered, they could help resolve a variety of long-standing scientific questions. For example, they could reveal the age and evolution of Mercury's crust, its mineralogical and geochemical composition and the nature of its gases.
RELATED STORIES
—Mercury is weird because of a 'hit-and-run' incident in its youth
—See Mercury's frigid north pole in extraordinary new images from the BepiColombo spacecraft
—9-mile-thick layer of solid diamonds may lurk beneath Mercury's surface, study hints
The origin of these samples is likely to remain a subject of continuing debate within the scientific community. Several presentations have already been scheduled for the upcoming Meteoritical Society Meeting 2025 in Australia. We look forward to future discussions that will further explore and refine our understanding of their potential origin.
For now, all we can do is make educated guesses. What do you think?
This edited article is republished from The Conversation under a Creative Commons license. Read the original article.
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Medscape
a minute ago
- Medscape
Nutrition Assistance Programs Combat Cognitive Decline
Nutrition assistance programs do more than fighting hunger. They also may help guard against age-related cognitive decline. Researchers found that people who participated in the US Supplemental Nutrition Assistance Program (SNAP) had slower cognitive decline over 10 years than peers who did not participate in the program. 'The chief policy implication of our study is that nutrition assistance programs like SNAP are not just anti-hunger tools — they are also public health tools that may help protect cognitive function and promote healthy aging,' lead author Linlin Da, MPH, PhD candidate, University of Georgia College of Public Health, Athens, Georgia, told Medscape Medical News . The study was presented on July 30 at the Alzheimer's Association International Conference (AAIC) 2025. Healthy Food, Healthy Brain Using the nationally representative Health and Retirement Study, researchers analyzed a racially and ethnically representative group of people aged 50 years or older. They compared 1131 individuals (mean age, 63 years) who were enrolled in SNAP in 2010 to 1216 individuals (mean age, 66 years) who were eligible for SNAP but did not participate in the program. 'Our study focused on SNAP — a real-world, policy-level intervention — rather than just individual food choices,' Da noted. As part of the study, memory and executive function were assessed every 2 years between 2010 and 2020 via telephone or web-based interviews. Individuals with an initial cognition summary score indicating cognitive impairment or dementia were excluded from the analysis. The researchers found that SNAP participants had a 0.10% slower decline in overall cognitive function ( P < .001 ), or 2-3 additional years of cognitive health over the 10-year period. 'For someone starting at a healthy cognitive score, this slower decline could delay reaching the threshold for mild cognitive impairment by nearly a decade,' Da noted in a conference statement. SNAP participants also had a slower decline in memory ( P < .001 ) and executive function ( P = .004 ) than peers not enrolled in SNAP. 'Our study is one of the first long-term, nationally representative studies to show that participation in a federal nutrition assistance program like SNAP is associated with slower cognitive decline in older adults,' Da told Medscape Medical News . Da said there are several biological and social mechanisms that may explain how SNAP participation slows cognitive decline, including improved nutrition. 'SNAP increases access to nutrient-dense foods that support brain health — such as fruits, vegetables, whole grains, and lean proteins. Better nutrition is linked to reduced inflammation, improved vascular health, and preservation of cognitive function over time,' Da explained. Reduced food insecurity and stress is another possibility. 'Chronic food insecurity is a significant source of psychological stress, which can negatively impact brain function. SNAP helps alleviate financial and emotional strain, leading to lower levels of chronic stress and potentially reducing harmful stress-related effects on memory and executive function,' Da said. 'We hope healthcare providers will see that potentially delaying cognitive impairment is another reason to help their patients-in-need secure access to food assistance,' co-author Suhang Song, PhD, assistant professor, Department of Health Policy and Management, University of Georgia College of Public Health, added in a conference statement. Equity Gaps While all racial and ethnic groups benefitted from SNAP participation, the protective effects on cognitive decline were smaller among non-Hispanic Black and Hispanic older adults compared with non-Hispanic White participants. There were 'racial and ethnic disparities in the cognitive benefits of SNAP, which points to important equity gaps in how nutrition policies may impact different populations,' Da said. 'We guess, even with SNAP, living in food deserts or areas with fewer healthy food options may limit the quality of nutrition people can access. This can especially affect Black and Hispanic communities, where structural barriers to healthy eating persist,' Da said. Commenting on this study for Medscape Medical News , Courtney Kloske, PhD, director of Scientific Engagement for the Alzheimer's Association, said it 'highlights the importance of nutritious foods and the impact that can have on the brain.' Maria Carrillo, PhD, chief science officer and medical affairs lead, Alzheimer's Association, noted that food insecurity can negatively affect cognitive function, and this is one of the first long-term studies to show that food assistance programs can positively impact cognition. 'Simple, everyday actions can make a difference in brain health and may even lower the risk of Alzheimer's disease and dementia. The Alzheimer's Association is committed to helping all people build these habits into their daily lives, including eating right, one of our 10 Healthy Habits for Your Brain,' Carrillo said in a statement.
Politico
32 minutes ago
- Politico
Trump's man in NASA
With help from Laura Kayali WELCOME TO POLITICO PRO SPACE. I got the first interview with NASA chief of staff Brian Hughes, the most senior Trump administration appointee at the agency. Read on for his take on the big changes happening at NASA. What's your take on the agency's direction? Email me at sskove@ with tips, pitches and feedback, and find me on X at @samuelskove. And remember, we're offering this newsletter for free over the next few weeks. After that, only POLITICO Pro subscribers will receive it. Read all about it here. The Spotlight Few space nerds could have predicted Brian Hughes' rise from Florida political operative and former National Security Council spokesperson to one of the most powerful figures at NASA. It started in June when billionaire Jared Isaacman was all set to take over as NASA administrator — only to see that job yanked away amid a bitter fight between his prospective boss, President Donald Trump, and his old business partner, Elon Musk. When the dust settled, Transportation Secretary Sean Duffy was left in charge as 'interim' NASA director, with a slate of big tasks. The agency must plan a mission to the moon and then Mars, deal with proposed budget cuts that decimate science research, and handle a staff exodus. It's still not clear who is leading space policy at the White House, and it may be months until NASA has a permanent administrator. Enter Hughes, who amid the turmoil, became the agency's chief of staff. Hughes, in his first public interview since taking the job in May, laid out what he sees as the agency's priorities, and responded to concerns about its future. Florida man: Hughes, who doesn't have a background in space, let alone NASA, is not your typical chief of staff — although he does say he's 'a proud member of nerds of America.' But Hughes brings along an important qualification. He's close to the White House, thanks to his role leading Trump's Florida campaign and his long history working with White House chief of staff Susie Wiles. To-do list: Hughes' top goals for NASA include pulling off a moon landing, supporting space commercialization, making progress toward sending astronauts to Mars and replacing the aging International Space Station. Moon vs. Mars: To the relief of moon advocates, Hughes suggested that NASA wouldn't follow along with Musk's dreams of ditching a moon mission in favor of Mars. NASA will pursue the 'moon as a pathway towards Mars, but really a focus on the moon in the short term,' he told me. Brain drain defense: NASA has seen nearly 4,000 employees walk out the door in the wake of proposed massive cuts and Trump administration efforts to thin the federal government. Hughes pushed back on the idea that the losses were devastating to the agency, even though most of the departures are senior level positions. 'I don't think there's any critical loss' of knowledge, he said. The agency is working to limit the impact by staggering departures, he added, and sixty percent of those who are leaving are at retirement age. 'Even when some senior people have left, there's an additional cadre behind them,' Hughes said. Budget battle: But the biggest storm clouds he'll likely face involve the coming battle between Congress and the White House over the NASA budget. The White House wants a cut of almost 25 percent, the biggest slash to the agency in decades. Congress would like to keep NASA funding where it is, and lawmakers aren't backing down. Hughes — perhaps hopefully — suggested that Congress and the White House could reach common ground as they work on the budget. 'It'll be like anything else — manage the consensus and respect the will of Congress,' he said. Galactic Government READY FOR LAUNCH: The U.S. has made progress in encouraging the mad scientists behind America's growing rocket launch industry. But the government needs to spread the financial love if it wants to keep costs low and the country secure, according to a new paper provided exclusively to me from the Progressive Policy Institute. One company — United Launch Alliance — used to dominate the launch industry. But the military and NASA now have more than a half dozen to choose from, including SpaceX, Rocket Lab and Blue Origin. Monopoly: While more choices are usually good for business, government buying patterns mean that the U.S. could end up with fewer launch providers than it needs, according to report author Mary Guenther, head of space policy at the Progressive Policy Institute, a left-leaning think tank. NASA, for example, could buy from a range of companies. But it still contracts with SpaceX for more than 60 percent of its missions. 'The agency needs to reassess its acquisition policies to avoid a relationship of convenience with SpaceX,' she wrote. It's regulation: Guenther also flagged a lack of launch infrastructure and a tough regulatory environment as an obstacle to the growth of the market. A lack of staffing at the office that licenses launches, for example, means the office must triage applications, a practice that Guenther said often favors SpaceX. Why it matters: The risk of relying on any one rocket company burst into view in early June during a rift between Trump and Musk, SpaceX's founder. Trump threatened to cancel government contracts with the billionaire, causing Musk to say he would cancel SpaceX's Dragon spacecraft, the only way for the U.S. to get to and from the International Space Station without relying on Russia. Fortunately for American astronauts, he did not follow through. Military THE TRUMP BUMP: While European governments remain highly dependent on U.S. weaponry, fears about Trump's unreliability are fueling them to try and buy local. That's especially true in the space domain. Rafał Modrzewski, the CEO of Finnish-based satellite company ICEYE, said in an interview that he saw a direct correlation between Trump's temporary decision to stop sharing space intelligence with Ukraine in March and a boost in government demand for his firm's military satellites. 'That was a huge wake-up call for countries contemplating whether they should own their own satellites or rather lease from allied nations and benefit from intelligence sharing,' he said. The European Commission has identified space-based intelligence, surveillance and reconnaissance as a key gap in European arsenals. Europe and beyond: ICEYE customers include NATO, Ukraine, Poland, Greece, Finland and Portugal. The company is also active in Japan, South Korea, the UAE and is hoping to increase its footprint in Brazil. Caveat: ICEYE satellites are mainly launched by American company SpaceX. Oops. The Reading Room Silicon valley enters the space race: POLITICO What is the FAA planning for rocket launch licenses?: Payload Musk ordered shutdown of Starlink satellite service as Ukraine retook territory from Russia: Reuters Air leak persists on Russian ISS segment: SpaceNews India safely launches a $1.5 billion satellite for NASA: Ars Technica Event Horizon MONDAY: The Mitchell Institute holds a webinar with Lt. Gen. DeAnna Burt of the Space Force. WEDNESDAY: The Intelligence and National Security Association holds a meeting on securing space. THURSDAY: The Federal Communications Commission holds an open meeting that will include discussion of space. The Progressive Policy Institute hosts a 'Space & National Security Happy Hour' at Hawk 'N' Dove. Photo of the Week MORNING MONEY: CAPITAL RISK — POLITICO's flagship financial newsletter has a new Friday edition built for the economic era we're living in: one shaped by political volatility, disruption and a wave of policy decisions with sector-wide consequences. Each week, Morning Money: Capital Risk brings sharp reporting and analysis on how political risk is moving markets and how investors are adapting. Want to know how health care regulation, tariffs or court rulings could ripple through the economy? Start here. (To sign up, add Financial Services to your policy interests and then add Morning Money to your newsletters.)
Forbes
2 hours ago
- Forbes
A Six-Planet Parade Is Coming — When To See It
planets of the Solar System abstract background, texture maps courtesy of NASA ( getty August is set to be a superb month for stargazers. The whole world may not go dark on Aug. 2 as the viral posts on social media would have it, but with the Perseid meteor shower and the full sturgeon moon, it's set to be a great month to be outside at night. However, the highlight will likely be a 'planet parade' (also called a 'planetary alignment') — six planets in the night sky at the same time, but only for those who get their timing spot on. Although the timings are not precise — with your location making a big difference to whether you'll see tiny Mercury or not — the highlights will be bright Venus, Jupiter and a brightening Saturn. Here's everything you need to know about the "planet parade" in August 2025. This planet parade — following on from one in the evening sky in February — will take place in the morning sky. That means you'll need to get up early to see it. The dates will vary depending on where you live, but this planet parade will take place between Aug. 10-20 in the eastern sky about an hour before sunrise. The planets Jupiter (L), Venus (C) and Mercury (R) are seen in an unusual conjunction setting over the Wupatki pueblo ruin on May 24, 2013 at Wupatki National Monument north of Flagstaff, Arizona. AFP PHOTO/Stan HONDA (Photo credit should read STAN HONDA/AFP via Getty Images) AFP via Getty Images During the first week, from Aug. 10-17, six planets will reside in the night sky, though only four will be visible — and only three will be easy targets. Venus and Jupiter will shine very close to each other above due east, with Mercury becoming visible beneath them closer to sunrise. On the morning of Aug. 12, Venus and Jupiter will be in conjunction, appearing 0.9 degrees apart. Saturn will be high in the south, with Neptune just above it (though not visible). Uranus will be high in the southeast (also not visible). From Aug. 17-20, the waning crescent moon will move past the planets, getting slimmer each day, with the highlight on Aug. 20 when a 9%-lit crescent moon will appear next to Venus. Observing Tips You don't need anything but your naked eyes to see this 'planet parade.' A large telescope is required to see Uranus and Neptune. However, since Mercury will be rising in the east, it will likely be harder to see in the haze of the horizon, so a pair of binoculars may make it easier (it will appear as a reddish dot). However, do be sure to stop using binoculars before sunrise because pointing them at the sun is very dangerous. Milky way arch over the Monument Valley, USA getty August is a perfect month for stargazing, with warm evenings and more hours of darkness than July. The highlight is the Perseid meteor shower on Aug. 12-13, though its rates of meteors will dip significantly this year because of a bright moon. The best time in August to go stargazing will be between Aug. 16-26, when bright moonlight won't be a factor. That's the best time to see August's true sky highlight — the Milky Way. You'll need to be in a dark sky destination — by using a light pollution map or staying overnight in an International Dark Sky Place . Look southeast as soon as it gets dark; the Milky Way streams through the Summer Triangle stars down to the galactic core near the constellations Scorpius and Sagittarius in the south. For exact timings, use a sunrise and sunset calculator for where you are, Stellarium Web for a sky chart and Night Sky Tonight: Visible Planets at Your Location for positions and rise/set times for planets. Wishing you clear skies and wide eyes.
