Haumea

Haumea is a curious denizen of the Kuiper Belt. Cigar-shaped, it's about 1,200 miles long, and astronomers have recently determined it is largely covered by crystalline water ice, as is at least one of its moons. The fact that it's crystalline water ice is important because water molecules so organized imply a nearby heat source. In the case of Haumea, scientists think the heat source likely is radioactive elements under the ice.

If the Haumea system is in fact rich both in water and in elements that could fuel nuclear reactors, it might become an important base in centuries to come as humans venture into the outer Solar System and beyond.