Saturn’s Moon, Enceladus, Is Our Closest Great Hope For Life Beyond Earth
“Cassini provided scientists with a wealth of data about Enceladus’ surface and the composition of its powerful plumes. This data showed evidence of a deep saltwater ocean with an energy source beneath Enceladus’ surface. The presence of water, warmth, and organic molecules are the necessary requirements for sustaining life as we know it. Water is proven to exist, while the tidal forces from Saturn provide the necessary heat. Based on observations of other bodies in the Solar System, Enceladus likely contains the raw ingredients for life as well. The suspected existence of all three hints at the possible presence of the precursors to amino acids in this vast subsurface ocean. Should we find extraterrestrial life on Enceladus – or in the geyser-like plumes erupting into space – the implications are almost incomprehensible.”
When you think about life beyond Earth, you likely think of it occurring on a somewhat Earth-like planet. A rocky world, with either a past or present liquid ocean atop the surface, seems ideal. But that might not even be where life on Earth originated! Deep beneath the Earth’s surface, geologically active hydrothermal vents currently support diverse colonies of life without any energy from the Sun. Saturn’s icy moon, Enceladus, has a subsurface ocean unlike any other world we’ve yet discovered. The tidal forces of Saturn itself provide the necessary heat, and also create cracks in the Enceladean surface, enabling massive geysers. This subsurface ocean rises hundreds of kilometers high, regularly resurfaces the world with a coat of fresh ice, and even creates the E-ring of Saturn. But most spectacularly, it may house actively living organisms, and could be the next-best world for life, after Earth, in the Solar System today.