Stardust comet dust resembles asteroid materials

Getting into the details: Stardust impact tracks and light gas gun impacts of sulfide in aerogel both display metal beads with sulfide rims indicating that GEMS-like objects in Stardust are generated by impact mixing of comet dust with silica aerogel. (left) Stardust GEMS-like material and (right) light gas gun shot GEM-like material. GEMS in cometary IDPs do not contain sulfide-rimmed metal inclusions. [Image credit: Hope Ishii, LLNL]