The largest object in the asteroid belt is an active world unlike any other in the solar system.
Nothing is normal on Ceres — least of all its mud volcanoes.
In new research published in Nature Astronomy, a large team of astronomers has laid out a new view of the weirdest world in our solar system. It seems that Ceres has had a busy last few billion years — including random smatterings of volcanism, but of a type seen nowhere else in the solar system.
http://astronomy.com/news/2018/09/volcanoes-of-mud-erupt-from-dwarf-planet-ceres