Ancient Martian Meteorite Teghaza 001 Offers New Insights into Early Mars
Scientists have dated the Sahara-found meteorite Teghaza 001 to at least 4.1 billion years, making it one of the oldest known Martian rocks and revealing evidence of early water interaction on Mars.
Researchers have identified Teghaza 001, a rose-colored meteorite recovered in Mali in 2022, as one of the oldest Martian rocks ever found on Earth. Laboratory analysis indicates the sample formed at least 4.1 billion years ago, within the first 400 million years of Mars’s history, and shows chemical signatures of water alteration in the planet’s early crust.
Planetary scientist Yang Liu of NASA’s Jet Propulsion Laboratory, lead author of the study published in Science, said the meteorite’s composition differs from previously examined Martian samples, providing a view of a previously unsampled crustal region. The rock, composed of eight fragments weighing a total of 798.5 grams, is a basalt that contains zircon crystals, which allowed precise dating.
The team employed a laser-based dating technique developed by coauthor Hayward Melton of the California Institute of Technology, reducing analysis time from weeks to a single day while preserving most of the material for further study. The method vaporizes tiny sample areas with a beam about one-tenth the diameter of a human hair.
Chemical analysis revealed a unique mix of calcium-rich minerals and an unusual oxygen isotope ratio, suggesting the rock interacted with water on early Mars. The findings may help scientists understand why Mars became dry while Earth retained water, with implications for planetary habitability.
Using compositional data from NASA missions, the researchers identified 13 possible source locations in Mars’s southern highlands. The discovery has attracted interest from the scientific community and collectors, including Darryl Pitt of the Maine Mineral & Gem Museum, which now holds the specimen.
"It is always nice to see a new visitor from Mars, and this one is ancient — one of the oldest from the planet, and older than any home-grown Earth rock," said Matthew Genge, associate professor of Earth and planetary science at Imperial College London, who was not involved in the study.
The study’s authors anticipate further investigations of Teghaza 001 will continue to shed light on the early evolution of Mars and comparative planetology.