A new NASA study indicates that icy worlds in the outer solar system, including Pluto, may actually have large liquid water oceans lurking underneath their surfaces. The study also found that the heat that is generated by the gravity of moons could keep the water oceans liquid for a long time, and could create conditions that would make extraterrestrial life possible there.

The study focuses on worlds found beyond the orbit of Neptune, which includes not just Pluto but also its moons. Known as Trans-Neptunian Objects, they are too cold to have liquid water on the surface, but can have water underneath if the conditions are right.

Tidal heating may be exactly the process needed to produce the circumstances necessary for these liquid water oceans to exist on TNOs like Pluto and Eris. It’s an important discovery because it suggests there are more places where extraterrestrial life could develop beyond the obvious places.

“These objects need to be considered as potential reservoirs of water and life,” said Prabal Saxena of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, lead author of the research published in Icarus November 24. “If our study is correct, we now may have more places in our solar system that possess some of the critical elements for extraterrestrial life.”