Lunar meteorite held in a researcher's hand. This 6-centimetre-long fragment of rock was originally part of a meteor that burnt up in the Earth's atmosphere, with the surviving fragments known as meteorites. The meteor in turn was originally part of the Moon, being ejected into space by an impact on the Moon's surface. Moon rocks are extremely old compared to Earth rocks, dating from between 4.5 and 3.2 billion years ago. Studying moon rock helps reveal the conditions present in the early solar system when the Moon and Earth were forming. This lunar meteorite, known as Dar al Gani 262 (DAG 262), was found in the Libyan desert on 23 March 1997. It is a 513 gram sample of anorthositic breccia.