Northwest Africa (NWA) 7397 Martian meteorite fragment (shergottite) with fusion crust, weighing 1.9 grams and measuring approximately 15 mm x 10 mm x 9 mm. Northwest Africa 7397 is a Martian meteorite found near Smara, Morocco in 2012. Classification was carried out by A. Irving and S. Kuehner at the University of Washington and 7397 was classified as a shergottite. A patch of fusion crust is visible on its surface.
Mars has captured our imagination like no other celestial body. From Gustav Holst, to H.G. Wells, to Edgar Rice Burroughs, to Kim Stanley Robinson, the Red Planet has inspired great works of art and thrilling tales of invasion and adventure.
Despite the numerous robot spacecraft that we have successfully landed upon its surface and the orbiters that have photographed its surface in amazing detail, and the rovers that have successfully roamed its ruddy surface, we have yet to engineer a mission to Mars that will return geological samples home for us to study. And yet, we do have actual pieces of the Red Planet here on Earth—pieces that have been exhaustively analyzed by academia and gazed upon in wonder by collectors, astronauts, and the curious. Those specimens arrived here as meteorites and they typically consist of igneous (volcanic) materials, making them very different in composition from most meteorites of asteroidal origin. These Martian meteorites were themselves blasted off Mars’ surface by other large impacts (likely very large asteroid fragments) and were identified in a most surprising manner—tiny pockets of gas trapped within representative examples were shown to be similar to the Red Planet’s atmosphere, as measured by the Viking robot landers.
Pieces of Mars are extremely rare and highly desirable—of approximately 61,000 meteorites that have been found on Earth, less than 200 have been identified as shergottite, or Martian. The class takes its name from the Shergotty meteorite that fell in India in 1865.
Terms and abbreviations used in our descriptions.