Discovered in Mali four years ago, a rose-colored Martian meteorite designated Teghaza 001 has been identified as an igneous rock formed more than 4.1 billion years ago, providing researchers with a chemical window into the ancient, water-rich crust of early Mars.
When an unusual rock turned up in the Sahara Desert in 2022, its exact origin and geological age remained entirely unknown. Weighing nearly 2 pounds (800 grams), the rose-colored specimen was later identified as a rare visitor from the Red Planet, joining a catalog of roughly 435 known Martian meteorites found on Earth.
Teghaza 001 Reveals Ancient Martian Geological History
Teghaza 001 stands out from its peers due to its distinct texture and unique suite of volcanic minerals.
Named Teghaza 001 after the salt plain in Mali where it was discovered, the meteorite is one of the three most ancient Martian meteorites found on Earth. Although invaluable, the other ancient meteorites provide more limited glimpses of Mars’ geological history. Teghaza 001 appeared to be a shergottite, which is the most common class of meteorite from the Red Planet. Although Yang Liu, the paper’s lead author at NASA’s Jet Propulsion Laboratory in Southern California, has seen plenty of those as an expert in planetary samples, she decided to take a peek anyway and noticed odd textures and unusual minerals she hadn’t seen before.
The meteorite’s distinctive mineralogy matches what NASA’s Mars Reconnaissance Orbiter has observed in the planet’s cratered southern highlands.
NASA researchers have identified a 4.1-billion-year-old Martian meteorite discovered in Mali’s Sahara Desert in 2022 as one of the three oldest known pieces of Mars found on Earth. pic.twitter.com/EsSgZ0fw9j
In-Situ Age-Dating Techniques and Water Alteration
Liu and her colleagues discovered zircon crystals in Teghaza 001, which record clues to a rock’s formation and can be used by geologists to precisely age-date a sample. Francois Tissot helped the researchers utilize an age-dating method.
As scientists noted in the study, this analysis of the rock provides a direct preview into the childhood of Mars, which was a wet childhood. Researchers discovered that Teghaza 001 had been in contact with water while it was still on Mars. This observation adds to the observations made in situ and in orbit of Mars by numerous probes and satellites. Liquid water likely circulated at its surface during that distant era and infiltrated deep into its soil.
Implications for Future Planetary Exploration
While meteorite finds in deserts and rocky terrain offer invaluable insights after being launched from Mars, the next step for scientists is to collect samples directly from Mars and bring them to Earth for analysis. By doing so, they will have access to the original material that has not been contaminated by the environment of our planet.