Planetary Meteorites
A Martian meteorite is a rock that was blasted off the surface of Mars by a powerful asteroid impact, traveled through space for millions of years, and eventually landed on Earth. These are genuine pieces of another planet — physically accessible without a spacecraft mission.
The Journey from Mars to Earth
1
Impact on Mars
A large asteroid strikes the Martian surface at high velocity. The energy of the impact excavates a crater and launches surface material into space. Unlike the Moon, Mars has gravity roughly 2.5 times stronger, requiring ejection velocities exceeding approximately 5 kilometers per second for debris to escape. Only the most energetic impacts generate material at that speed.
2
Transit through space
Once free of Martian gravity, the fragment orbits the Sun as a small rocky body. Cosmic ray exposure ages measured from isotopes that accumulate during transit indicate that most Martian meteorites spent between 1 and 20 million years in space before reaching Earth, though some have much shorter transit times. During this journey the rock is bombarded by cosmic radiation, leaving a measurable isotopic record of its time in space.
3
Entry and recovery on Earth
When the fragment intersects Earth's atmosphere, it decelerates rapidly and its outer surface melts, forming fusion crust. Most Martian meteorites are recovered from Antarctica or hot desert environments, where dark fusion-crusted rocks are visually distinctive against pale ground. The arid conditions of desert recovery regions also provide favorable preservation for the minerals and volatile signatures used in classification.
How Scientists Prove Martian Origin
Confirming that a meteorite came from Mars requires a converging set of evidence. The most definitive comes from a discovery that could not have been anticipated before the Space Age.
Tiny pockets of gas trapped inside certain Martian meteorites match the composition of the Martian atmosphere as measured by NASA's Viking landers in 1976. The match is exact and unique. No other source produces that combination of gas ratios.
This atmospheric fingerprint, particularly the isotopic ratios of noble gases and nitrogen, provides a direct link between the meteorite and Mars that cannot be explained by any other origin. It is the equivalent of a planetary barcode, and it was recognized as Martian in 1983 when researchers compared the gases trapped in the shergottite EETA 79001 against Viking's data.
Trapped atmospheric gas
The most definitive marker. Shock-melted glass in shergottites traps Martian atmospheric gases at the moment of the ejecting impact. The isotopic ratios of argon, nitrogen, and carbon dioxide match Viking lander measurements exactly and differ from all other meteorite types and from Earth's atmosphere.
Oxygen isotopes
Martian rocks plot at a distinct position on the oxygen three-isotope diagram, clearly separated from Earth, the Moon, and all major asteroid groups. This is one of the primary screening tests for planetary origin.
Mineral chemistry
The FeO/MnO ratio in pyroxene and olivine is highly diagnostic. Martian minerals consistently plot in a field distinct from terrestrial rocks and from meteorites of asteroid origin. This ratio is controlled by the planetary bulk composition and does not change with weathering.
Crystallization ages
Most Martian meteorites are young by solar system standards. Shergottites typically crystallized between 150 million and 600 million years ago, consistent with volcanic activity on a geologically active planet. Asteroid-derived meteorites are almost always older than 4 billion years.
Water alteration minerals
Several Martian meteorites contain carbonates, sulfates, and phyllosilicates formed by liquid water. The chemistry of these alteration minerals is consistent with Martian water chemistry inferred from orbital and surface observations.
Types of Martian Meteorites
Martian meteorites are grouped as the SNC group, named for their three founding members. Each type reflects different geological environments on Mars.
Shergottites
Most common Martian type • Basaltic and lherzolitic rocks • Crystallized 150 to 600 million years ago
Volcanic rocks formed from Martian magmas. Named after the Shergotty meteorite that fell in India in 1865. The most abundant Martian meteorite type, subdivided into basaltic, olivine-phyric, and lherzolitic shergottites based on texture and mineralogy. Their young crystallization ages indicate Mars was volcanically active in geologically recent times. Most contain the shock-melt glass that traps atmospheric gases used to confirm Martian origin.
Nakhlites
Clinopyroxenites • Formed in ancient lava flows • Crystallized ~1.3 billion years ago
Coarse-grained rocks dominated by the pyroxene mineral augite. Named for the Nakhla meteorite that fell in Egypt in 1911. All known nakhlites share nearly identical crystallization ages around 1.3 billion years and similar textures, suggesting they may originate from the same lava flow on Mars. Many contain secondary minerals formed by interaction with liquid water, providing some of the strongest mineralogical evidence for aqueous activity on Mars.
Chassignites
Dunites • Olivine-dominated • Extremely rare
Olivine-rich rocks equivalent to terrestrial dunite. Named for the Chassigny meteorite that fell in France in 1815. Only a handful of chassignites are known, making them among the rarest of the already rare Martian types. They represent a deep mantle source on Mars and share the same approximately 1.3-billion-year crystallization age as the nakhlites, suggesting a possible co-origin.
ALH 84001
Orthopyroxenite • Oldest known Martian rock • Crystallized ~4.09 billion years ago
The only known specimen of its type. An ancient orthopyroxenite from the earliest period of Martian history, when liquid water was present at the surface. Became globally famous in 1996 when NASA researchers announced possible evidence of past microbial life in its carbonate globules. The biological interpretation has not been confirmed by subsequent research, but ALH 84001 remains scientifically exceptional as the oldest known Martian rock and the only sample of early Mars available for study.
Regolith breccias
Surface material • Mixed lithologies
A small number of Martian meteorites are polymict breccias representing disrupted and mixed surface material rather than coherent igneous rock. They sample the Martian regolith and may contain material from multiple geological units. NWA 7034 and its pairings, sometimes called Black Beauty, are the best-known examples and contain the highest water content of any Martian meteorite yet analyzed.
How Rare Martian Meteorites Are
<400
Confirmed Martian meteorite specimens worldwide
<0.1%
Of all recovered meteorites are Martian
~270 kg
Estimated total known mass of Martian material
Every confirmed Martian meteorite specimen on Earth represents ejected material from a single impact event that generated enough velocity to escape Martian gravity, survived millions of years in space, survived atmospheric entry, was recovered, and underwent laboratory confirmation. Each step eliminates most candidates. The result is a global supply measured in hundreds of specimens and a few hundred kilograms of material, distributed across research institutions and private collections worldwide.
What Martian Meteorites Tell Scientists
No robotic mission has yet returned samples from Mars. Martian meteorites are the only physical samples of the planet available for laboratory study anywhere on Earth. They have been used to establish the age of Martian volcanism, identify minerals formed by liquid water, measure the composition of the Martian atmosphere at the moment of ejection, and probe the deep interior chemistry of a planet we have not yet visited with a sample return mission.
Because each meteorite was ejected from a different, unknown location on Mars, the global collection samples a broader range of Martian geology than any single landing site. Together they have shaped the scientific understanding of Mars as a geologically complex, formerly water-rich world.
Before buying: what to verify
Every legitimate Martian meteorite has a published Meteoritical Bulletin entry with its SNC classification confirmed by laboratory analysis. Verify the name at lpi.usra.edu before purchasing. The listing should include the exact classification (e.g. shergottite, basaltic), total known weight, and a direct Bulletin link. No verified classification means no confirmed Martian origin.
Browse Martian Meteorites
Frequently Asked Questions
How do scientists know a meteorite came from Mars?
The most definitive evidence is trapped atmospheric gas. Shock-melted glass in Martian meteorites seals in Martian atmosphere at the moment of ejection. The isotopic composition of these gases matches Viking lander measurements exactly and is unique to Mars. Oxygen isotopes, mineral chemistry, and young crystallization ages all provide supporting evidence.
How rare are Martian meteorites?
Fewer than 400 confirmed specimens exist worldwide, representing roughly 270 kilograms of material. They make up less than 0.1% of all recovered meteorites. Individual specimens from small-find or scientifically significant types can be exceptionally scarce on the collector market.
Can collectors legally own Martian meteorites?
Yes. Martian meteorites can be legally bought and sold when they were lawfully recovered. Ownership is legal in most jurisdictions. Every legitimate specimen has a published Meteoritical Bulletin entry that can be independently verified.
What is the difference between a shergottite and a nakhlite?
Both are Martian meteorites but from different geological environments. Shergottites are younger basaltic volcanic rocks that crystallized between 150 million and 600 million years ago. Nakhlites are coarser-grained clinopyroxenites that crystallized around 1.3 billion years ago, likely from a single ancient lava flow. Nakhlites also tend to contain more evidence of water alteration.
Are Martian meteorites more valuable than lunar meteorites?
Generally yes, per gram. Martian meteorites are rarer than lunar meteorites overall, and the identification story involving the Viking atmospheric match gives them an additional layer of scientific narrative. Prices vary significantly by type, total known weight, and specimen quality. Both categories are substantially more expensive than common chondrites.
What is Black Beauty?
NWA 7034 and its paired specimens are nicknamed Black Beauty because of their dark color and high water content. They are polymict breccias representing Martian surface regolith rather than a coherent igneous rock. NWA 7034 contains the highest water content of any Martian meteorite analyzed and records the ancient Martian crust in a way no other known specimen does.
