Thanks NASA’s Cassini mission, scientists have been able to confirm that underneath the icy crust of one of Saturn’s moons, Enceladus, lies a global ocean. Naturally, that begs the question could there possibly be something living in that ocean. When looking for life in our solar system, the first thing we look for is water (H2O). That is the most important element that has to be present and if we find it, we know we are on the right track.
Now when it comes to Enceladus, not only did we find some water, we essentially found an entire planet full of it. But even though water is a great place to start, it doesn’t guarantee life, especially after you consider that Enceladus is so far away from the sun that sunlight doesn’t reach it making photosynthesis impossible, and there is also no oxygen on Saturn’s moon. After factoring all of that, the whole life on Enceladus thing isn’t looking too good. But what if we can find examples of life thriving is the most exotic and desolate parts of Earth? That’s where there’s hope.
Scientists have discovered microbes in parts of our planet where sunlight doesn’t reach, and oxygen isn’t present because photosynthesis can’t take place. Sound familiar? There are three ecosystem here on Earth that could be the basis for life on Saturn’s moon—two of them are based on methanogens, that belongs to an ancient bacterial group related to the “rugged survivalists” archaea. These are found in volcanic rocks along the Colombian river as well as in Idaho Falls, so they are real! These microbes pull their energy form the chemical interactions of different rocks, while the microbes in third ecosystem located deep within a South African mine, gets energy from radioactive decay in rocks. This is how we know life is feasible on Enceladus, but how would life start.
This is the trickier question to answer because we don’t even know exactly how life started on Earth. But what we do have our theories of how life originated on Earth and we can see which of those theories are applicable to Enchiladas. There are currently two theories that meet this criteria, the Primordial Soup theory and the Deep Sea Vent theory. But there are still more pieces of to this puzzle that we need to have a definitive answer, including analyzing the organic compounds in the plumes released by Enceladus’ aquifers and figuring out what is the energy source powering its aquifers. It looks like we are really close to the answer, and even if we find that life most likely isn’t present on Enceladus, that journey to that answer was definitely a fun one.
