The origin of one of the oldest Martian meteorites


The history of the planet Mars can also be researched on Earth: with the help of Martian meteorites. A research group has now re-examined one of these, with the scientific identifier NWA 7034, and determined where exactly the rock came from on the red planet. The volcanic material was ejected from Mars five to ten million years ago when an asteroid hit it. The basaltic breccia itself is around 4.5 billion years old, making it one of the oldest known Martian rocks, as a team led by Anthony Lagain from Curtin University in Perth explains in the journal Nature Communications. Future studies of the region of origin on Mars could therefore reveal more about the origin of the red planet.

Based on the meteorite’s chemical signature and structure, Lagain and his team determined its possible origins. To do this, they programmed an algorithm that evaluates surface images of Mars and identifies smaller craters. In this way, the team found about 90 million craters, some as small as 50 meters in diameter.

© NASA (detail)

Martian meteorite NW 7034 | The chunk was found in the Sahara in 2011. Initially, experts put the age at around 2.1 billion years. They are now assuming around 4.5 billion years.

In the case of NWA 7034, the working group found: An impact that created the approximately 40-kilometer-wide Khujirt crater about 1.5 billion years ago brought the basaltic breccia to the surface. Another impact of an asteroid five to ten million years ago then ensured that the rock was thrown into space as a meteorite and then fell on earth. The structure, which astronomers have dubbed Karratha Crater, like Khujirt Crater, lies northeast of the Terra Cimmeria and Terra Sirenum regions of Mars.

According to the results of the study, this area would be a worthwhile place for further investigation to find out more about the formation of Mars. “We assume that the clasts contained in the breccia [Gesteinsbruchstücke] are representative of the origin from the region of Terra Cimmeria and Terra Sirenum. This makes this region a relic of early formation processes of the Martian crust and an area of ​​great interest for future missions.



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