New Mineral Found in Moon Rock

This wasn't part of the Apollo hoard the astronauts brought back from the Moon. The moon rock was a meteorite, one of many offworld samples found on Earth. On it was a speck of an iron silicide (Fe₂Si) that had never been found in nature before. The mineral formed in the exceptional conditions of space weathering, in which high-energy impacts vaporize large amounts of the rocks involved. Minerals like the new one, named hapkeite, are the result of deposition out of this vapor. They're one more ingredient in the regolith of hard-vacuum planets. The discovery was reported in PNAS yesterday.