 Analysis left the scientists astounded because they are pure elemental sulfur crystals, which up until now they thought needed specific Earth-like conditions to form, and there seems to be a whole field of them. Curiosity's project scientist Ashwin Vasavada said, quote, it shouldn't be there, so now we have to explain it. Michael Toscano, WTOP News. Coming up on WTOP, homes in northern Virginia are selling a little bit slower. It's 8.43.