Poseidonal Subtype
Europan Type planet or moon. If the world is massive enough and experiences severe enough tidal stressing, the icy surface and mantle may be melted to a depth of hundreds of kilometers, and the world will be enveloped in a thick atmosphere. Surface ice will be present, but spotty, giant icebergs adrift on a global ocean. Life is almost always present, but rarely very advanced.
Text by John M. Dollan in his Planet Classification List
Initially published on 19 December 2001.