Ceres

Image of Ceres taken with the Dawn spacecraft
Credit:  NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/Justin Cowart

​Ceres is a dwarf planet that is the largest object orbiting within the asteroid belt.

It is made of the mainly ice and rocky minerals and by itself makes up a third of the mass of the whole asteroid belt! It is 930 kilometres (580 miles) across, about half the size of our own Moon.

Ceres was discovered way back in 1801 by the Italian astronomer Giuseppe Piazzi, and it remains the only dwarf planet in the inner Solar System, where it takes 4.6 years to orbit the Sun.

The NASA spacecraft, Dawn, began orbiting the dwarf planet in March 2015 and sent back a huge amount of data, finding out a lot about the dwarf planet - for example it is composed of ice and rock, and the surface seems to have icy volcanoes on it!