A meteorite discovered in the Sahara has been identified as a fragment of Mars dating back around 4.1 billion years. Researchers say its minerals and chemical composition offer clues to conditions on the planet during its earliest history, including the possible presence of water.
The findings come from a study involving the University of New Mexico, NASA’s Jet Propulsion Laboratory, Caltech and UCLA, published in the journal Science. The meteorite, named Teghaza 001, initially drew attention because its texture, mineralogy and composition were unusual compared with other known Martian meteorites.
University of New Mexico meteorite researcher Carl Agee noticed similarities between the sample and “Black Beauty,” a meteorite associated with the Martian crust. Teghaza 001 also has unusual oxygen-isotope values and areas with high concentrations of manganese oxide. Researchers study manganese oxide on Mars because it can indicate environments that may have been habitable, though its presence does not demonstrate that life existed there.
The team’s analysis suggests Teghaza 001 formed in a Martian environment that may have been more Earth-like than the planet is today. That could have included surface water and a denser atmosphere, and perhaps a protective magnetic field. These are interpretations of the meteorite’s evidence, not proof of past life on Mars.
Researchers dated zircon crystals in the rock using uranium-lead analysis. The results place the meteorite at about 4.1 billion years old, making it, according to Agee, the oldest known Martian meteorite made from lava rock. It formed during the planet’s pre-Noachian period, an early era that Agee described as a particularly plausible time for primitive life to have been widespread, if it existed on Mars.
Teghaza 001’s distinct chemistry and mineralogy may also point to a part of Mars not yet visited by a rover. Remote-sensing data narrowed its possible origin to the planet’s southern highlands, perhaps near the Hellas basin, JPL researcher Yang Liu said. The researchers suggest that future Mars missions could investigate this region for further samples.
Sources: t3n.