Deep inside a tiny moon of Saturn, sandwiched between its icy shell and rocky core, is a sea of water the size of Lake Superior.
Over the past few years, NASA’s Cassini probe—in orbit around Saturn since 2004—has made repeated flybys of Enceladus (pronounced: en-SELL-a-dus), ever since photographs of geysers, shooting ice crystals, emerged in 2005. This hinted at the possibility of an underground ocean.
Just over 300 miles wide, Enceladus is now turning out to be the best candidate for harboring life elsewhere in the solar system, even more than Mars.
Discussion on the possibility of extraterrestrial life in the solar system centers on four bodies: Mars, Enceladus, Europa (a moon of Jupiter), and Titan (another moon of Saturn.) But so far, only Enceladus is known to possess the four essential ingredients for life, at least, as it exists on Earth: liquid water, energy, carbon, and nitrogen.