Small moon of Uranus may have once had a subsurface liquid water ocean 

 Surface features of Uranus' icy moon Miranda point to the existence of a once deep ocean, one that still may exist today.  

https://cdn.mos.cms.futurecdn.net/javqeFgcCcM5bTp8vAKcEf.jpg

https://www.space.com/uranus-moon-miranda-subsurface-ocean-voyager-2