What is a Martian Meteorite?
A Martian meteorite is a rock that formed on the planet Mars and was then ejected from Mars by the impact of an asteroid or comet, and finally landed on the Earth. Of over 61,000 meteorites that have been found on Earth, just over 130 are known to come from Mars as of 2017, making them some of the rarest material on Earth, along with lunar meteorites.
Analysis comparing the in-situ science conducted by Mars landers and rovers such as Viking, Spirit, Opportunity and MSL have proved beyond doubt that these rocks originate from Mars. Ahead of any human mission to Mars, these are the only way scientists have of studying the Martian surface in any great detail.
Martian meteorites roughly fall in to three main categories
- SHE = Shergottite
- NAK = Nakhlite
- CHA = Chassignite
And then two sub categories
- OPX = Orthopyroxenite (ALH 84001 is the most famous example of this)
- BBR = Basaltic Breccia (NWA 7034 also known as Black Beauty is the most famous example of this)