Secrets of the dwarf planet Ceres have been revealed by two studies published in the journal Nature. Jim Drury has more.
Dwarf planet Ceres, filmed from NASA's Dawn spacecraft. Researchers from the Max Planck Institute for Solar System Research suggest the bright spots - more than 130 in all - are a type of salt. They say these were probably created when water-ice sublimated, due to asteroid strikes. A separate study reveals evidence of ammonia-rich clays, raising the possibility that Ceres originated in the outer solar system. It's currently in the main asteroid belt between Mars and Jupiter. The studies were published in journal Nature.