Teghaza 001 meteorite formed at least 4.1 billion years ago and samples Mars’s early crust

Zircon grains in the 800-gram stone give a uranium-lead age of 4.111 ± 0.013 billion years and a less precise rubidium-strontium age of about 4.24 billion years agrees, but if those clocks were reset by heat or fluids the rock is older still.

Peer reviewed · Laboratory analysis of one meteorite · Ages may be minimums

A rose-coloured meteorite found in the Sahara in 2022 is a slowly cooled igneous rock from Mars that formed at least 4.1 billion years ago, a team led by Yang Liu of NASA’s Jet Propulsion Laboratory reports in Science. Its minerals, chemistry and texture match no other Martian meteorite, and the authors read it as a piece of the planet’s early crust from a mantle source with a primordial composition. Only two other Martian meteorites reach back this far, and both are harder to interpret. The catch: the dated minerals may record a later reset, not the rock’s birth.

Evidence at a glance

Is this a big deal?

For Mars geology, a solid step rather than a shift. Researchers already pictured early Mars with water and a thick ancient crust across its southern highlands. What they lacked was a dated, whole igneous rock from that era with its minerals intact, and this is it. Where on Mars it formed, and exactly when, stay open.

What scientists found

Teghaza 001 is a gabbroic diorite rich in plagioclase, the companion paper reports: a coarse-grained rock that cooled slowly underground rather than erupting as lava. Its pyroxene crystals carry thick exsolution bands, a texture that takes slow cooling to form. The find weighs about 800 grams, nearly 2 pounds, and is named for the Teghaza salt plain in Mali, near where it was picked up in 2022.

Three clocks give its age. Zircon grains dated by uranium-lead give a weighted mean of 4.111 ± 0.013 billion years, and apatite dated by lead-lead gives 4.124 ± 0.028 billion years. An in situ rubidium-strontium isochron on the silicate minerals comes out at 4.238 ± 0.208 billion years: less precise, but consistent. The Science abstract calls it “a slowly cooled igneous rock that formed at least 4.1 billion years ago” with a composition, mineralogy and texture distinct from every other Martian meteorite.

The abstract adds two results. The parent magma came from a mantle source with a primordial composition, separate from the sources of other Martian meteorites, and the altered minerals and oxygen isotopes show the rock reacted with fluids enriched in oxygen-18 while still on Mars. JPL says its mineralogy matches what the Mars Reconnaissance Orbiter sees in the cratered southern highlands, where the paper lists 13 candidate source regions.

How they found it

Carl Agee and Karen Ziegler at the University of New Mexico’s Institute of Meteoritics first confirmed the stone was Martian from its oxygen isotopes, a planetary fingerprint. It looked like a shergottite, the most common kind of Martian meteorite, and Liu nearly declined to examine it, JPL says. Then came the odd textures, and zircon. That mineral locks in uranium as it grows, and the lead that uranium decays into gives an age.

Caltech’s François Tissot applied an in situ rubidium-strontium method to a piece smaller than a fingernail, dating single mineral grains in place instead of dissolving the sample. Its agreement with the zircon and apatite ages is what makes 4.1 billion years hard to dismiss.

Think of each clock as a car’s trip meter. It shows the distance since someone last pressed reset, not the car’s total mileage. Heat or fluids can reset radiometric clocks, and the companion paper reports signs of alteration on Mars: sodium-rich rims on zircon and plagioclase, and heavily altered pyroxene cores. If one event reset all three clocks at once, the rock is older than 4.1 billion years. The analogy breaks here: a trip meter is reset on purpose, and nobody knows whether this reset happened at all.

Why it matters to you

Nothing in daily life changes. This is about origins: what a rocky planet’s crust looked like in its first few hundred million years, and whether water moved through it. Mars formed about 4.5 billion years ago, NASA says, so if its history were one day long, Teghaza 001 crystallised in roughly the first two hours and most other Martian meteorites in the last three. For the bigger question, see was Mars habitable in the past?

What the evidence does not show

It does not make Teghaza 001 the oldest Martian material on Earth. Zircon grains in the Black Beauty meteorite NWA 7533 are 4.428 ± 0.025 billion years old. Teghaza 001 is the oldest Martian meteorite that is a single igneous rock with a full set of minerals.

It does not show where on Mars the rock formed; the orbital match points to regions, not a crater, and Liu told Scientific American that finding the launch site is a separate, difficult task. It says nothing about life. And every conclusion rests on one stone.

How this fits what we already knew

Before this year, two Martian meteorites reached back into the planet’s first half-billion years. Allan Hills 84001, found in Antarctica in 1984, has a lutetium-hafnium age of 4.091 ± 0.030 billion years, Thomas Lapen and colleagues reported in 2010, and is almost entirely one mineral, orthopyroxene. Black Beauty, NWA 7034 and its paired stones, is a breccia: fragments, including those 4.43-billion-year zircons, cemented into a rock about 2.09 billion years ago and reheated long afterwards, dating work led by Agee in 2013 and William Cassata in 2018 found. The shergottites, most Martian meteorites, crystallised 150 to 570 million years ago.

The companion paper used the same stone to measure hydrogen isotopes in its apatite. By 4.1 billion years ago, Mars’s water held at least about twice as much deuterium relative to hydrogen as Earth’s seawater, which the authors read as rapid loss of hydrogen to space from the young atmosphere. Related SciQuest coverage: tracking data that point to a hotter mantle beneath southern Mars, and crystals that record Earth’s early mantle, on how zircon and apatite clocks are read.

Independent perspective

SciQuest has not yet interviewed anyone outside the author team. Arya Udry, a planetary scientist at the University of Nevada, Las Vegas, who was not involved, told Scientific American that much remains to be learned from the meteorite and that not knowing where it came from strengthens the case for returning samples from Mars. When the companion paper appeared in June, James Day of the Scripps Institution of Oceanography, also not involved, told Live Science by email: “I would caution that all of these arguments would have been based on a single small stone.”

How other headlines framed it

• Scientific American led with the “oldest known Mars rock” and the reviewer’s “Rosetta stone” line, and was the only outlet to carry an independent voice.
• Reuters, read via Cyprus Mail, framed it as possibly the oldest Mars meteorite and leaned on what it means for habitability, while saying the findings do not show life existed.
• CBS News stayed close to the JPL release: a rose-coloured rock, one of the three most ancient, altered by water.
• Interesting Engineering called the southern-highlands regions a “chemical twin” and said the water cycle was “confirmed”, stronger than the sources support.
• Sci.News gave the two ages, about 4.11 and 4.24 billion years, and the comparison with ALH84001 and NWA 7034.

Black Beauty’s older zircons mean “oldest Mars rock” needs the qualifier “single igneous rock”, which SciQuest uses.

What happens next

Liu told JPL: “We’ve only scratched the surface.” The main mass is held by the Maine Mineral and Gem Museum and a 22 g classification sample by the University of New Mexico, so other laboratories can request material. Open questions: which of the 13 candidate regions it came from, whether the 4.1-billion-year clocks record crystallisation or a reset, and how its primordial mantle source relates to those of younger Martian rocks. Tissot’s group hopes to apply its small-sample rubidium-strontium method to more Martian meteorites and returned samples, JPL says.

In one sentence

Teghaza 001 is a slowly cooled piece of Mars’s crust at least 4.1 billion years old, dated by three agreeing clocks and altered by water on Mars, but it is one stone of unknown origin and its true age could be older.

Read next

• Mars is 200–400 °C hotter beneath its southern highlands: the region Teghaza 001 may have come from.
• Was Mars habitable in the past? The question this rock’s water record feeds into.
• Crystals hint Earth’s mantle was oxidizing before the Great Oxidation Event: zircon and apatite as records of an early planet.

Sources and disclosure

1. Liu Y, Saper LM, Bell EA, Ma C, Li H, Hu J, Guan Y, Melton H, Cruz-Uribe AM, Yap TE, Tissot FLH, Bucholz CE, Ziegler K, Agee CB. “A Martian meteorite that formed ≳4.1 billion years ago samples Mars’ early crust and mantle.” Science, published online 29 October 2026. doi:10.1126/science.adz5646 (abstract read via Crossref; main text paywalled). Preprint: ESS Open Archive, 14 April 2026.
2. Saper L, Liu Y, Guan Y, Ma C, Bell EA, Agee CB. “A Noachian hydrosphere component in the 4.1-Ga Martian meteorite Teghaza 001.” Science Advances 12(24): eaea3420, 10 June 2026. doi:10.1126/sciadv.aea3420 (open access; full text read via Europe PMC). Source of the zircon, apatite and rubidium-strontium ages, rock type, alteration textures and sample custody.
3. NASA Jet Propulsion Laboratory. “NASA-funded Study Details One of Oldest Mars Meteorites Ever Found.” News release 2026-079, 29 October 2026 (source of all author quotes, the mass, find details, the count of about 435 Martian meteorites and the 13 candidate regions).
4. Lapen TJ et al. “A younger age for ALH84001 and its geochemical link to shergottite sources in Mars.” Science 328, 347 (2010). doi:10.1126/science.1185395.
5. Humayun M et al. “Origin and age of the earliest Martian crust from meteorite NWA 7533.” Nature 503, 513 (2013). doi:10.1038/nature12764.
6. Agee CB et al. “Unique meteorite from early Amazonian Mars: water-rich basaltic breccia Northwest Africa 7034.” Science 339, 780 (2013). doi:10.1126/science.1228858; Cassata WS et al. “Chronology of martian breccia NWA 7034 and the formation of the martian crustal dichotomy.” Science Advances 4, eaap8306 (2018). doi:10.1126/sciadv.aap8306.
7. NASA Science. “Mars: Facts” (formation about 4.5 billion years ago).
8. Coverage read for framing and independent comment: Scientific American, Reuters via Cyprus Mail, CBS News, Interesting Engineering, Sci.News, Live Science (13 August 2026, on the companion paper).

Disclosure: This article was drafted with AI assistance and checked against the sources above. The Science main text was not accessible to SciQuest; every number is taken from the published abstract, the open-access companion paper, the JPL release or the earlier peer-reviewed papers cited. The research was NASA-funded. Calculations by SciQuest: 800 g ÷ 453.6 g per lb ≈ 1.8 lb; on a 24-hour scale of 4.5 billion years, 0.4 billion years ≈ 2.1 hours and 0.15–0.57 billion years ≈ 0.8–3.0 hours. The graphic is a SciQuest original drawn from the cited ages. Spotted an error? See our corrections policy.