Smivs writes: "Titan, the haze-shrouded moon of Saturn, displays tantalising evidence of ice volcanoes.
Two regions of Titan have been seen recently, by the Cassini spacecraft, to undergo clear changes in brightness.
This activity, and radar images hinting at flow-like structures, suggest the presence of volcanoes, scientists say.
Rather than erupting molten rock, Titan's "cryovolcanoes" are thought to ooze a slurry made of water ice, ammonia and methane.
"These flows would come out as a thick slurry," said Dr Rosaly Lopes, a Cassini radar team investigation scientist. "They can be thick because cryomagma would be viscous, similar to lava flows on Earth.""