A meteorite found in Mali is giving scientists an unusually old sample of Mars. Researchers say Teghaza 001 formed at least 4.1 billion years ago, when the planet’s crust was still taking shape. Minerals in the rock also record changes associated with water, but they cannot tell scientists exactly where on Mars it began.
The rock was recovered from the Sahara Desert in 2022. In an account of the research published on 29 October 2026, NASA’s Jet Propulsion Laboratory described it as one of the oldest Martian meteorites found on Earth.
How do researchers know it came from Mars?
The University of New Mexico’s research team compared the rock’s oxygen isotopes, which act like chemical fingerprints, with those in other Martian meteorites. Later analysis found tiny zircon crystals that helped researchers establish its great age. The team also studied individual mineral grains, preserving much of this rare sample for future work.
What can it tell us about water?
According to JPL, the meteorite’s minerals indicate that Martian water altered the rock around 4.1 billion years ago, after the material originally formed. That makes Teghaza 001 a useful record of how rock and water interacted early in Mars’s history.
The finding does not show that life existed on Mars, or establish what conditions prevailed across the whole planet. It describes evidence in one meteorite. Researchers can test that interpretation further as they study more of the sample.
Where on Mars did it come from?
The precise source remains unknown. The rock’s mineral makeup resembles material observed in parts of Mars’s ancient southern highlands, but a match is not a confirmed birthplace. An impact eventually launched the material away from Mars before it reached Earth.
For scientists, the value of Teghaza 001 is the rare opportunity to examine an ancient piece of Martian crust directly. Its age, minerals and water-related changes offer several lines of evidence about the planet’s early history, with important questions still open.
A microscopic view of a slice of Teghaza 001 used to study the Martian meteorite’s minerals. Credit: NASA/JPL-Caltech.
