Ancient Martian Meteorite Found in Sahara Dates Back 4.1 Billion Years
Scientists say the Sahara-found meteorite Teghaza 001, dated at least 4.1 billion years old, offers new evidence of early liquid water on Mars and may be the oldest known Martian rock on Earth.
A reddish igneous rock recovered in the Sahara in 2022 has been identified as a Martian meteorite that formed in the planet’s crust at least 4.1 billion years ago, researchers reported. Named Teghaza 001, the specimen is composed of coarse-grained gabbro containing feldspar, pyroxene and zircon crystals with uranium, allowing its age to be determined through uranium-lead decay analysis.
Planetary scientist Yang Liu of NASA’s Jet Propulsion Laboratory described the meteorite as “a witness to a time when Mars was likely warmer and wetter than it has been for most of its history.” The rock’s chemistry indicates it interacted with water while cooling and crystallizing beneath the Martian surface, suggesting that liquid water percolated into the crust more than 4.1 billion years ago.
Liu, lead author of the study published in Science, said Martian meteorites are the only physical samples from the planet, providing a basis for understanding early Mars formation and assessing its past habitability. Co-author Lee Saper of NASA’s Ames Research Center added that the findings support the idea that early Mars possessed the ingredients and conditions needed for life, though they do not confirm its presence.
Teghaza 001 was discovered in eight fragments near the Malian village of Bir Chali, with the largest piece roughly the size of a fist. Its isotopic signatures of oxygen and hydrogen point to water percolating into the deeper crust, similar to processes on Earth. The rock may have originated in Mars’s southern highlands, possibly near the Hellas Basin, before being ejected by an impact, traveling through space, and eventually landing in the Sahara.