A second meteorite of probable lunar origin has been found among the several thousand meteorites recovered from Antarctica. It is number 791197 from the Yamato collection, which was recovered by an expedition from the Japanese Institute of Polar Research, Tokyo. The first meteorite of probable lunar origin (ALHA 81005) was identified by Brian Mason in 1982.
Some meteorites may be leftover rock fragments from the nucleo-synthesis event that produced the solar system. It is also believed that some meteorites are the result of other meteorite impacts on either the moon or on Mars and that these samples were ejected into earth orbit. However, it is not clear if these samples could have escaped the gravity on Mars.