A couple of months back the Cassini spacecraft took the following spectacular image of Saturn. This image is actually composed of 165 individual images in total all stitched together and taken over several hours, the reason it looks so weird compared to other images of Saturn you have seen in the past is this was taken during an artificial solar eclipse, the team positioned Cassini on the opposite side of Saturn to the Sun.
Not only can you see Saturn, some of its moons and the rings lit up by the sunlight passing through them you can also make out our tiny planetary home the Earth and its satellite the Moon, which can be seen as a pale blue dot just above the outer most bright ring (the A ring) on the left hand side of Saturn.
Cassini took this picture of the southern hemisphere of Enceladus and found warm patches on the ice (the greenish tinge on the image), we know the surface of Enceladus is quite young because of the lack of impact craters, however from this information we could deduce that Enceladus is still geologically active and like Jupiter’s satellite Europa may have a liquid ocean beneath the ice covered surface. The real killer piece of evidence came for this later on in the mission; Cassini actually photographed an eruption taking place on Enceladus’ surface. This makes it only the 3rd known body in the solar system to be geologically active.
Water is actually being blown off the world and out into space and these eruptions are emanating from the cracks in the surface. This material is actually responsible for forming Saturn’s E ring, the large outmost ring in the above image. Due to the energy required to do this Enceladus probably has a body of liquid water beneath the surface. That gives us the two main ingredients we need for life, water and heat. Could there be life under Enceladus’ surface? We have similar conditions here on the bottom of our oceans, you can go for miles and miles across the baron seabed until you come across an undersea thermal vent and find it positively teeming with life, they extract all the energy they need from the vent. Astro-biologists consider these sorts of environments the most likely places for life to exist out in the solar system.
If Enceladus does have life on it, some of that life is surely being blown off into the E ring, what a wondrous thought that is; Saturn’s rings are actually partially composed of frozen microbes.