Ancient Martian Meteorite Found in Sahara Offers Clues to Early Water

A rose-colored meteorite discovered in the Sahara Desert in 2022 has been identified by NASA-backed scientists as a 4.1-billion-year-old chunk of the Red Planet. Weighing nearly two pounds and recovered in Mali, the rock was named Teghaza 001 after the salt plain where it was found.

Researchers utilized a pioneering age-dating method to study tiny zircon crystals embedded in the meteorite. By measuring radioactive elements within these crystals, scientists were able to reconstruct the rock's history and establish that it dates back approximately 4.1 billion years. This makes it one of the three most ancient Martian meteorites ever found on Earth, and the oldest known Martian igneous rock identified to date by a significant margin.

The analysis revealed that the rock is made of a unique mix of volcanic minerals that were altered by water about 4.1 billion years ago. According to the research published in the journal Science, this water activity occurred beneath Mars' surface during the planet's earliest development, indicating that the ancient environment was considerably different and potentially more Earth-like than today's cold, dry conditions.

Dr. Carl Agee, director of the Institute of Meteoritics at the University of New Mexico and a co-author of the study, noted that the meteorite exhibits anomalous oxygen isotopes and domains with high levels of manganese oxide. Manganese oxide is a compound that can act as a byproduct of biological activity or indicate environments conducive to life. Agee stated that the sample likely came from a time in the Pre-Noachian period when the Martian environment featured surface waters, a denser atmosphere, and a protective magnetic field.

Unlike most known Martian meteorites, which formed hundreds of millions of years ago and typically consist of dry desert-era debris, Teghaza 001 offers a single, unadulterated rock type from a much earlier epoch. Scientists compare its value to a Rosetta Stone for Mars, providing a rare snapshot of the planet's early crust, mantle, and formation processes.

By comparing the meteorite's chemical and mineral makeup to orbital data collected by NASA's Mars Reconnaissance Orbiter, researchers were able to narrow down its potential origin to 13 sites in Mars' ancient southern highlands. Investigators hope this connection will help guide future exploration, landers, and rovers to regions of the Martian crust that have never been sampled before.