6. Ceres' Bright Spots
In 2015, the Dawn spacecraft discovered some weird bright spots, shining out from the surface of the dwarf planet, Ceres. The spots, which are four times brighter than the rest of the planet's surface, baffled scientists. Were these bright dots made of ice? Flames? The city lights of an intelligent alien race? Early speculation thought that it might be the result of
outgassing, but study of hi-res images found that they were more likely to me highly reflective objects on the planet's surface. Unfortunately for the alien lovers out there, these are unlikely to be great space mirrors or extraterrestrial solar panels, and more likely to be boring old salt. Pretty salt, but salt nonetheless.