Tridymite is a high-temperature, low-pressure form of quartz that is extremely rare on Earth, and it wasn’t clear how a chunk of it ended up in Gale Crater on Mars, the home of NASA’s Curiosity rover. (a) Location of the Buckskin mudstone sample (red star) in Gale Crater, Mars; (b and c) images from the Mars Hand Lens Imager onboard the Curiosity rover of (b) Lamoose, a local float block adjacent to Buckskin within the Murray formation showing...
