In fact, water molecules (which are made up of one oxygen atom and two hydrogen atoms) are abundant in planetary systems that form around other stars, according to NASA. Water molecules have been found around the 20-million-year-old star Beta Pictoris, where a huge disk of dust and gas points to collisions between comets, asteroids and young planets.
Much earlier, during its 1979 flyby of Jupiter, NASA’s Voyager 1 spacecraft discovered that the surface of the moon Europa was a cracked mass of water ice, as if it were composed of icebergs floating above a hidden sea. As he continued his journey to Saturn, he took measurements of that planet’s huge moon, known as Titan, and showed us that this icy world had a thick atmosphere that could host lakes or seas of liquid hydrocarbons on the cryogenic surface; being the only object, apart from Earth, where clear evidence of stable liquid bodies on the surface has been found. Thus, this moon that harbors seas and hydrocarbon precipitation, could harbor a “strange alien life based on methane”, as confirmed by NASA.
The moon Titan is a somewhat particular place in our solar system, because it has an ocean in the subsoil and also has liquid hydrocarbon lakes on the surface, hence the possibility of some kind of methane-based life form has been opened.
NASA’s Galileo mission, at the time, also hinted that two other Jovian moons, Callisto and Ganymede, were also home to oceans. And the Cassini space probe found abundant evidence for multiple ocean moons during all its years of studying the Saturn system. Both Galileo and Cassini deliberately slammed into their respective gaseous subjects to avoid any possibility of bio-contamination of the moons. Galileo’s self-immolation occurred in 2003, and Cassini’s fiery end in September 2017.
Thus, the Earth is not the only oceanic world in our solar system as we have seen. Do you dare to take a walk through those ocean worlds of our galactic neighborhood?