A 54-pound Martian meteorite, NWA 16788, the largest ever found on Earth, sold for $5.3 million at a Sotheby's auction. Discovered in Niger, it's significantly larger than the next biggest Martian meteorite. While some express concern about its private sale, a planetary scientist notes that meteorite collecting fuels scientific research, and a reference sample has been secured for study. The high price reflects the rarity of Martian meteorites—only around 400 have ever been found.

Prepared by Olivia Bennett and reviewed by editorial team.