Martian meteorite By Matt Young December 19, 2022 12:00 MST Photograph supplied by Dan Phelps. Martian meteorite – Mr. Phelps tells us, "I bought a small Mars meteorite: northwest Africa 12269 0.395 grams. About a centimeter wide and slightly more long. Very thin." The meteorite was discovered in 2018 in an unknown location in northwest Africa. The photograph is from the documentation that came with the meteorite.