Every year, more than 5,000 tons of material with cosmic origins lands on Earth’s surface, with as much as 15,000 tons of this “space dust” making its way into the atmosphere but vaporizing during reentry.

The resulting rain of micrometeorites that reaches our planet consists mostly of tiny objects anywhere from 30 to 200 micrometers in size, based on past studies. But what are the origins of these large volumes of material that accumulate over time as they shower the Earth throughout the year?

According to new research, evidence for one potential source of this cosmic debris has now been found: it could be coming from unidentified near-Earth objects.

Space Dust with Unknown Origins

The problem with tracing the origins of space dust is that most of it that makes its way into Earth’s atmosphere doesn’t survive the intense conditions of atmospheric entry, and those tiny bits that do—known as cosmic spherules—are reshaped as they melt from the friction they encounter while falling.

Although their original mineral structure is compromised as well as their shape, there are a few isotopes—namely oxygen—that these spherules maintain that scientists can use to help trace their origins. Based on their chemical “fingerprints,” cosmic spherules are placed into different groups by planetary scientists, with many being able to be traced back to known varieties of meteorites and other sources.

Among these groups, around ten percent fall into a category possessing unusually small quantities of the isotope oxygen-16. This category, known as Group 4, doesn’t appear to match any known meteorite group—the implication, therefore, is that some of this cosmic debris may originate from an unidentified variety of near-Earth objects.

New Clues to the Origins of Uncorrelated Space Dust

Now, according to new research by Matthias Van Ginneken and colleagues, there are at least some ways that the origins of these spherules can be determined, one of which involves their orbital parameters.

In one case, the team writes in a recent study published in Science Advances, “the mineralogical and textural properties of a subset of cosmic spherules do provide information on the orbital parameters of their precursors, including eccentricity and encounter velocity.”

This group of materials, which is dubbed “CumPo” based on its material consistency of cumulate olivine porphyritic, is “characterized by clustered olivine phenocrysts that increase in size from one side of the spherule to the other,” the team writes.

In short, this unique class of spherules points to equally unique orbital characteristics that may be associated with what the research team surmises could be atypical types of near-Earth objects, or NEOs, that could be near enough to our planet to provide a likely source.

A particular clue offered by these objects is that some of them may have undergone unusually high entry speeds, as evidenced by their surface texture. One factor that could potentially account for this is that they may have entered Earth’s atmosphere at angles consistent with objects possessing high orbital eccentricity.

More Clues from Antarctica

As with past studies, researchers were able to retrieve several samples of these CumPo cosmic spherules from Antarctica, which provides a pristine environment that helps to facilitate their discovery and collection. However, another source location had been far less remote: urban rooftops, where a large amount of cosmic dust lands every year.

With the aid of electron microscopy and microprobe chemistry studies, Ginneken and colleagues examined the mineralogy, chemistry, and textures of these spherules, as well as the oxygen isotopes they contained.

What they found indicated an entirely new subset of spherules, which possess significant amounts of cumulate olivine rich in sulfur, garnering the name “SCumPo.” This unique new class of samples has links to the “Group 4” class and their minimal inclusion of oxygen-16. Other unusual similarities they possess are an overall absence of magnetite and a low presence of nickel in their olivine crystals, paired with an abundance of iron-nickel sulfur and a significant amount of sulfur present within glasses produced from vitrification.

Intriguingly, some spherules appeared to show a combination of signatures that were both poor in oxygen-16 in some areas, while rich in the isotope in others. This suggests that these cosmic materials had likely been mixed from two separate original sources, since such conditions could not be otherwise explained through natural processes.

“We interpret this as strong evidence that the SCumPo precursors were composite materials containing at least two different components,” the team writes in their study. Then, by running numerical simulations of crystal settling to help determine the likely entry speeds of these materials, and thereby their eccentricities while in orbit, the team determined that the settling of olivine is most consistent with entry speeds of as much as 17 kilometers per second, and likely no more than 14 kilometers per second—speeds that would be consistent with NEOs, as opposed to asteroids originating from the main-belt.

Evidence for an Unknown Class of Space Objects

Based on their findings, the team believes that unsampled meteorites from the CM, CO, and CY classifications of carbonaceous chondrites—a group of primitive, carbon-rich meteorites containing some of the oldest materials in our Solar System—are the likely sources for these cosmic materials.

“Given that we have linked their composition to the CM-CO-CY clan of carbonaceous chondrites, it is plausible that their parent body was a primitive carbonaceous asteroid that migrated onto an Earth-crossing orbit—attaining comet-like orbital parameters,” the team writes.

“For instance, one might consider the disrupted fragments of a thermally altered but water-bearing asteroid (like the CY group) that evolved into near-Earth space,” they add.

Although still only inferred from their studies, the team suggests the existence of a hypothetical new variety of NEOs based on the samples they studied, which are unlike any variety of meteorites currently known on Earth.

“These findings point to a previously unsampled, primitive, sulfide-rich CY-like near-Earth asteroid, which represents a ‘missing’ meteorite parent body that contributes distinctive ¹⁶O-poor cosmic dust to Earth,” the team writes, noting that any future confirmation of the existence of this unknown class of meteorites would represent “a pivotal discovery.”

The team’s new paper, “¹⁶O poor cosmic spherules from near-Earth CY chondrite asteroids,” appeared in Science Advances.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

When you think of an asteroid impact, you’re probably imagining something like the cataclysmic event that nearly wiped out the dinosaurs. In an astonishingly rare event, a rock the size of the island of Manhattan could come hurtling from deep space towards Earth and destroy the world.

On the contrary, asteroids are generally leftover debris from the primordial solar system that didn’t become part of a larger body, like a planet or moon, and they’re not particularly rare. Scientists estimate that there are about 1 billion asteroids and comets classified as near-Earth objects, or NEOs. NEOs are generally much smaller than the asteroid that killed the dinosaurs. They range from weakly held-together piles of rubble 200 meters (700 feet) across, to the minuscule 2024 BX1, approximately 44 centimeters (17 inches) across. 

For several decades, astronomical surveys of the sky have looked for these asteroids. NASA’s Center for Near-Earth Object Studies (CNEOS) Fireball and Bolide Database has records of over 1,000 incidents of objects colliding with our planet since the mid-1990s. Among these is a set of 11 objects that scientists detected before they hit Earth, known as imminent impactors. Finding imminent impactors allows scientists unique opportunities to study the smallest building blocks of the solar system, enabling them to learn more about asteroid composition, structure, and history.

A team of scientists recently conducted a study on how the newly built Vera Rubin Observatory could detect more imminent impactors before they strike Earth. They examined the CNEOS Fireball and Bolide Database impact records spanning February 1, 1994, to January 1, 2026, for records of the asteroids’ coordinates, velocities, and the energy they released at the time of collision. 

They found that 343 NEOs met this criterion, including 5 known imminent impactors. Using these recorded data, they reconstructed the objects’ pre-impact characteristics. The team predicted the asteroids’ orbital paths from the recorded coordinates and velocity. Assuming the objects were spherical, they estimated the size from velocity and impact energy. From this information about the asteroids’ state before impact, the team could then simulate whether the Rubin Observatory would have detected them. 

When small asteroids hit Earth, they mostly burn up in the atmosphere, producing a bright flash that is relatively easy to spot compared to when they are in space. The Rubin Observatory can see objects up to 10 billion times dimmer than the brightest star in the night sky, Sirius. To predict if the Rubin Observatory can detect dim NEOs, the team used the solar system simulator SORCHA. SORCHA takes an observatory’s specifications and the physical properties of the NEOs and uses these to determine whether the observatory could detect them. It also estimates the measured sizes and speeds of the NEOs, and predicts when the observatory would have seen them. 

At the Rubin Observatory, an imminent impactor is considered discovered if it’s observed at least 3 separate times over 15 days before hitting Earth. So this team applied this same criterion to their simulation. They found that of their 343 impactors, SORCHA estimated that the Rubin Observatory would have discovered 14 of them before impact. 

They also found that SORCHA predicted 4 additional impactors that could have been observed at least once, potentially allowing scientists to search other telescope data for evidence of their existence in pre-collision images. Based on these results, the team estimated that the Rubin Observatory could find 4% of all objects longer than 1 meter (3 feet) before they hit Earth. This percentage of discovery translates to 1 to 2 imminent impactors detected every year, at least double their current discovery rate.

The ability to more consistently find imminent impactors would allow researchers to study the smallest pieces of the solar system in detail and to draw general conclusions about the properties of objects that could potentially collide with Earth. This would also allow scientists to more accurately calculate the orbits of imminent impactors, determine where more meteorites land to recover them, and keep tabs on the extremely rare but more hazardous large impactors for planetary defense initiatives. So, humanity can learn more about the ancient solar system, and hopefully avoid going the way of the dinosaurs while doing so!

The post How many asteroids can we detect before they hit Earth? appeared first on Sciworthy.

En levant les yeux vers le ciel nocturne dans la nuit de lundi à mardi, peut-être avez-vous eu la chance d’apercevoir une brève mais intense traînée de lumière. Mais de quoi s’agissait-il ?

La scoperta: All'interno del meteorite marziano NWA 8171, i ricercatori guidati dalla geologa planetaria Tanya Kizovski della Brock University hanno individuato per la prima volta in assoluto alcuni granelli di granato (nello specifico, andradite).

I geologi svelano un legame inaspettato tra un antichissimo e catastrofico impatto meteoritico e le più grandi riserve di metallo prezioso del pianeta.

A Martian meteorite fragment containing unexpected grains of mineral could hold clues to the Red Planet’s geological history, according to an international team of researchers.

Prior to the team’s new paper, which was published in Geochemical Perspectives Letters, the red mineral garnet had never been observed in any martian rock sample. Now, the meteorite discovery provides scientists with new clues to Mars‘ extreme past conditions, over its 4.5 billion-year history, which could include hidden magma sources or ancient impact events.

Garnet and Geology

Although the gemstone garnet can come in many colors, it is best known for its dark red varieties, which were historically popular in ancient Egypt, Rome, and Victorian England. Beyond its beauty, the rock is important for the record it keeps of its birth, providing Earth’s geologists with information on our planet’s tectonic forces, ore-forming processes, and the fluid-rock interactions of the crust and mantle.

Similarly, the small grains of garnet discovered in the meteorite sample contain important data for reconstructing the forces that forged the Red Planet long ago.

“The findings add a striking new dimension to our understanding of the geology of Mars and open an exciting new window into the evolution of our planetary neighbour,” said co-author Professor James Darling.

“This discovery is going to expand our knowledge of the geologic processes that are possible on this planet,” said lead author Tanya Kizovski, Assistant Professor of Earth Sciences, from Brock University in Canada. “This new garnet-bearing rock type could give us clues to how Mars has changed throughout its history and new insights into the ancient environments that could have formed the garnet and related minerals.”

Mars Meteorite NWA 8171

The garnet fragments were discovered in a tiny Martian meteorite sample held in the Royal Ontario Museum’s collection, designated NWA 8171, discovered in northwest Africa. Kizovski led the team in analyzing the sample’s mineral and chemical composition after identifying it as a unique piece within the collection.

“This little section of the meteorite looked really interesting, and the chemistry was a bit odd,” Kizovski said. “At first, we assumed it was a mineral called pyroxene, which is very common, but then we decided to take a second look.”

The international effort brought in researchers from Italy’s University di Trieste and the UK’s Open University, utilizing the Royal Ontario Museum’s laser equipment and the University of Portsmouth’s Electron Microscopy and Microanalysis Unit.

Having never been observed in any previous Martian sample, the researchers were surprised to identify garnet in the meteorite’s composition. From their analysis of the sample’s chemistry and mineralogy, the researchers began to consider how the unexpected garnet could have formed.

“Garnet is a classic example of a mineral often found in metamorphic rocks on Earth,” Kizovski said. “The process of metamorphism transforms igneous or sedimentary rocks into a new form through exposure to extreme heat, high pressure, or hot fluids.”

“On Mars, the heat and pressure needed to produce garnet through metamorphism could have come from the impact of a meteorite hitting the surface of Mars, magma rising up into the Martian crust, or both,” Kizovski continued.

Explaining Martian Garnet

While garnet provided geologists with some data about how it formed, this is not like the point of origin stamped on a manufactured good. It is possible that the garnet was deposited on Mars during an earlier meteorite impact, only to later travel through the solar system again, or that it was created by a heretofore unknown magma source on Mars.

Only further analysis of the garnet’s isotopic signatures will allow the researchers to determine whether the mineral formed on Mars or elsewhere. Unfortunately, to do so, the team would have to destroy a portion of this rare and precious sample, which measures only 0.8 by 0.5 millimeters to begin with.

“Measuring oxygen isotopes from the garnet-bearing rock type itself would help to confirm if it is Martian in origin or from an exotic meteorite impactor,” Kizovski said.

“Isotopes are a collection of atoms with equal numbers of protons and electrons, but different numbers of neutrons,” she added, “which was avoided thus far due to its rarity, as it may be the only garnet-bearing Martian rock we have for study.”

A few members of the team are continuing their study of the sample by comparing their findings to Martian data collected by rovers and orbital platforms. Further insights, they hope, may help them discover more about how the garnet could have formed, and what its presence means for the deeper history of the Red Planet.

The paper, “Expanding Mars’ Lithologic Diversity: Discovery of a Garnet-Bearing Clast in NWA 8171,” appeared in Geochemical Perspectives Letters on June 16, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.

A lunar meteorite links ancient impacts on the moon, Earth and asteroid Vesta.

Planetary scientists analyzing a lunar meteorite known as Northwest Africa (NWA) 12593 have uncovered evidence of an asteroid impact that occurred 3.5 billion years ago on the Moon, helping to reconstruct a period of intense bombardment that left lasting marks across the inner Solar System.

The post Lunar Meteorite Preserves Evidence of Colossal Asteroid Strike appeared first on Sci.News: Breaking Science News.

A rare meteorite found in the Sahara Desert has revealed evidence of a giant ancient world that once existed in our solar system but later disappeared. Scientists believe this lost world formed about 4.5 billion years ago, during the early days of the solar system. It may have been as large as the Moon or […]

The post Rare Sahara meteorite uncovers a hidden planet from the early solar system appeared first on Knowridge Science Report.

A meteorite discovered in Africa could be evidence of a lost protoplanet that once orbited our Sun, according to researchers at the University of Colorado at Boulder.

In a recent paper published in Earth and Planetary Science Letters, the team revealed evidence of an ancient protoplanet that may have been as large as Mars based on simulations of how the meteorite sample may have formed.

The four-and-a-half-billion-year-old world carried an unexpected geological makeup, which the researchers say casts doubt on common assumptions regarding planetary evolution.

Protoplanetary Demise

According to the UC Boulder team, the massive protoplanetary body collided with another object four and a half billion years ago, shattering it completely. This is the first definitive evidence of a lost protoplanet in our solar system, based on analysis of the angrite meteorite NWA 12774, a shard of that planetary embryo recovered from the Sahara Desert.

“It’s incredible to think there was once a world this large,” said lead author Aaron Bell, an assistant research professor in the Department of Earth Science at CU Boulder. “We only know it existed because a few fragments of it happened to land on Earth. These meteorites preserved evidence of a completely different pathway through which early planets developed.”

A Rare Meteorite Sample

Angrites, a rare type of volcanic rock, serve as a record of our solar system’s distant past. These rocks began forming only a few million years after the solar system’s birth, making them valuable evidence of this early era. However, they are extremely rare and difficult to find.

NWA 12774 is one of only 68 angrite samples identified among more than 80,000 meteorites cataloged by scientists. Given its rarity, the discovery could potentially reshape how researchers understand these ancient rocks.

Until now, scientists had assumed that angrites originated from relatively small asteroids less than 124 miles (200 kilometers) wide, based largely on their chemical composition. Large rocky planets such as Earth and Mars contain significant amounts of silicon dioxide, while angrites contain very little of the compound.

Unexpected Meteorite Discovery

Researchers began to reconsider those assumptions when they identified clinopyroxene in the meteorite sample. This mineral, commonly found in Earth’s crust and mantle, appeared unusually rich in aluminum, suggesting that it formed under significant pressure deep within a planetary body.

To investigate this unusual characteristic of NWA 12774, the University of Colorado Boulder team recreated the conditions under which the sample could have formed. Their analysis revealed that pressures of at least 17.5 kilobars were required to produce the aluminum-rich clinopyroxene found in the meteorite. For comparison, one kilobar is roughly equivalent to the pressure at the deepest part of Earth’s oceans, near the bottom of the Mariana Trench.

Rethinking Meteorite Origins

The researchers’ discovery proved that at least this particular angrite sample could not have formed inside a small meteorite, as a body with a radius of at least 621 miles would be required to generate the pressure needed to produce the crystals. 

Additional evidence suggested the parent body may have been even larger. The crystals’ sharp edges and delicate internal structures indicate they likely formed at relatively shallow depths beneath the surface. Reconciling both the high-pressure conditions and the shallow formation depth suggests that the parent body may have ranged in size from the Moon to Mars.

“There are many meteorites sitting in drawers that haven’t been thoroughly studied, so there were likely more of these protoplanets we don’t know about,” Bell said.

Exactly what happened to this ancient world remains uncertain, but researchers believe it was likely destroyed in a massive collision early in the solar system’s history. Fragments of that lost protoplanet may have later contributed material to other bodies, potentially including Earth itself.

“The materials that formed the angrite parent body are fundamentally different from the ingredients of Earth and Mars,” Bell concluded. “It points to a distinct and separate evolutionary path in planetary formation in the early history of our solar system.”

The paper, “High-Pressure Clinopyroxene in Northwest Africa 12774 and New Geobarometric Evidence for a Planetary Embryo-Sized Angrite Parent Body,” appeared in Earth and Planetary Science Letters on July 1, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.

Pour sa 36e édition, le Festival d’Astronomie de Fleurance réunit au cœur du Gers scientifiques, passionnés et grand public du 31 juillet au 7 août 2026. Résolument tourné vers les familles, il inaugure des formats inédits et prépare les festivaliers à vivre un moment céleste exceptionnel :...

Krotite is a cosmic relic, one of the oldest minerals in the Solar System.

The Northwest Africa (NWA) 12774, an angrite meteorite discovered in the Sahara Desert, likely in Mauritania, appears to be a fragment of a vanished protoplanet, offering the strongest evidence yet that a large planetary body formed and was later destroyed during the Solar System’s chaotic infancy.

The post Meteorite Found in Africa Preserves Evidence of Long-Lost Massive Protoplanet appeared first on Sci.News: Breaking Science News.

Un meteorite ha esploso sopra il nord-est degli USA, generando boati e preoccupazione. Scopri le caratteristiche e l'importanza della sorveglianza.

Dopo l'ipotesi di un terremoto, a fare chiarezza ci hanno pensato gli esperti dell’American Meteor Society