Teghaza 001, a witness to ancient Martian crust
· BehindLines newsroom
A meteorite found in the Sahara in 2022 offers a particularly ancient sample of Mars. In a study published on 29 October in Science, researchers describe Teghaza 001, a rock that formed more than 4.1 billion years ago, according to NASA. NASA presents the work as a chance to study a part of the Martian crust that is rarely represented in collections.
The University of New Mexico took part in identifying the material: its researchers compared the oxygen isotopes of the rock with those of other Martian meteorites to establish where it came from. According to the university, tiny zircon crystals made it possible to date this igneous rock. The date of the study is recent; the date of the rock goes back to the earliest period of Mars's history.
Teghaza 001 stands out in particular because it represents a single type of rock. The university contrasts this with Black Beauty, another Martian meteorite described as an assembly of many rock types. According to the university, this difference gives researchers a less mixed sample from which to interpret an ancient geological environment.
The minerals also carry signs of interaction with water. According to NASA, the team's dating results point to alteration by Martian water around 4.1 billion years ago, which suggests the rock formed earlier still. The agency's release does not put a figure on the interval between these two events. A JPL note also describes alteration minerals that formed on Earth, so not every alteration in the sample is Martian. These traces tell us about geological processes; they are not an observation of Martian life.
By comparing the sample's composition with orbital observations, the team proposes several possible source regions in the southern highlands. No precise launch site has been established. A mineralogical match guides the search but does not replace a sample taken on the spot.
The meteorite's value therefore lies in the possibility of combining laboratory analyses with maps of Mars. The presentations by NASA and the university describe the same collaboration, not two separate discoveries. Further analyses will have to clarify what this sample reveals about the diversity and evolution of the Martian crust.