After years of studying the dwarf planet Ceres, researchers are starting to see light on where could the ice in Ceres be coming from. with NASA's Dawn mission, it was found out that the axial tilt of Ceres could be the answer.
In an article in the Space Daily, NASA scientists found out that the axial tilt, the angle at which it spins while revolving around the sun, of dwarf planet Ceres highly varies over the past 24,500 years. At one glance this period of time can be too long, but astronomers emphasized that this is too short to see that kind of dramatic changes in a dwarf planet like Ceres.
According to the official press release of NASA, this uniqueness of Ceres' axial tilt could also be the possible reason why ice exist in the dwarf planet. Anton Ermakov, a researcher at the NASA's Jet Propulsion Laboratory, shared that Ceres possesses craters which stays in shadows for a long period of time. With this, water deposited in these areas freeze therefore forming ice particles in Ceres.
NASA further explained that throughout the span of 3 million years, Ceres had diverse tilt histories where it tilted from 2 degrees up to almost 20 degrees. Researchers also cited that the last time that Ceres exhibited its maximum tilt was 14,000 years ago. To get a better idea, NASA made an analogy that Earth is tilted at 23.5 degrees which is responsible for the different seasons in the different parts of the planet. With Ceres being tilted currently at 4 degrees, NASA explains that the dwarf planet doesn't experience these kind of seasons.
NASA also imparted that when the axial tilt is too small just like what Ceres has, several parts of the dwarf planet don't receive direct sunlight which translates to the heavy presence of ice. As calculated by NASA's Dawn mission, around 2,000 square kilometers of Ceres are covered in shadows.
