The Martian rock, known as NWA 16788, is 70% larger than the next biggest piece of Mars that has been recovered, according to the auction house.

A meteorite that is the largest known piece of Mars on Earth has sold for $5.3 million, with taxes and fees, to an anonymous bidder at a Sotheby’s New York auction Wednesday.

The largest piece of Mars ever found on Earth was sold for just over $5 million at an auction of rare geological and ...