Ceres is the king of the asteroid belt, being the largest object in that region of the Solar System, and the Dawn spacecraft has shown it to be a very interesting world. While it is relatively small, classified as a dwarf planet, and very cold being so far from the Sun, there are hints that it has been surprisingly geologically active in the past and perhaps still is. Superficially it resembles the Moon or Mercury, gray and covered in craters. But there are also canyons, hazes, and unusual bright spots. Those spots have become a focus of much interest for scientists, and now new studies indicate that they appear to change in brightness from day to night, and may be evidence of ongoing activity inside Ceres.
There now might be a definitive answer to a puzzle which has intrigued both scientists and the public for some time: What are those odd bright spots on the dwarf planet Ceres? A new study suggests they are a type of salt, originating from a subsurface layer of briny water-ice. Another study points to the existence of ammonia-rich clays on Ceres.
The Dawn spacecraft has sent back the best view yet of the main bright spots in Occator crater on the dwarf planet Ceres. The new image has a resolution of 140 meters (450 feet), and was taken from an altitude of 1,470 kilometres (915 miles).