One researcher has even proposed a way for life to survive on the giant Saturnian satellite. It is too cold for organisms to survive on the surface of Titan, where temperatures are about -178C (-289F).

But David Grinspoon of the Southwest Research Institute says organisms could occupy specific niches, such as hot springs. They could use acetylene, in reaction with hydrogen gas, to release enough energy to power metabolism, and possibly to heat their environments.