Far-off alien planets covered in vast oceans might be common in our Milky Way galaxy, scientists find.
“Ocean worlds” are terrestrial planets that have significant amounts of water either on their surfaces or in a subsurface sea. Right here in our own solar system, Saturn and Jupiter host moons that fall under this watery category. For example, Enceladus, Saturn’s geyser-spewing moon, has a massive, global ocean made up of liquid saltwater that lies just below its icy surface. But how common are these “ocean worlds” throughout the cosmos?