If you need to think about another space object from the Solar System, except for Earth, where life could appear, perhaps the first answer that pops into the mind is planet Mars. It’s way too hot on Mercury and Venus. Jupiter and Saturn aren’t even solid planets, while it’s too cold on Uranus and Neptune.
But how about the moons of the Solar System? Just like Earth has its own natural satellite, it’s also available for other planets. In fact, Saturn and Jupiter have many more moons than Earth does. Saturn is the champion with 82 discovered moons. Jupiter, on the other hand, has 79 moons. It’s obvious that astronomers need to explore those natural satellites of the gas giants of our Solar System as well. Life could have developed there already.
Alien life existing on Jupiter’s moon Europa?
Europa, one of Jupiter’s numerous moons, might already be hosting some life forms. Scientists rely their hunch on the assumption that liquid water exists on Europa as well, according to The Guardian.
Jupiter’s moon might have entire pools of salty water hiding beneath its surface. Scientists believe so after they discovered giant parallel ridges that stretch across long distances on the moon and are similar to surface features from the Greenland ice sheet.
Dustin Schroeder from Stanford University explained as The Guardian quotes:
Liquid water near to the surface of the ice shell is a really provocative and promising place to imagine life having a shot,
The idea that we could find a signature that would suggest a promising pocket of water like this might exist, I think, is very exciting.
Scientists, in general, still need to answer a lot of crucial questions about the emergence and evolution of life. But the existence of liquid water is a ‘must’ for life as we know it to develop as well.