![]() (Ocean Networks Canada - CC BY-NC-SA 2.0)There has been a lot of focus on searching for life on Mars, especially since evidence of flowing water was announced recently. And while it looks like Mars once had lakes, rivers and possibly oceans, that was billions of years ago. Colonies like this under Earth's oceans, which can thrive without light, indicate that life might be able to develop under the surface of oceans known to exist on moons elsewhere in the solar system. ![]() In fact, some have suggested that these types of vents are where life could have first appeared on Earth. If similar vents exist on the ocean floors of ice moons, could life be there as well?Ĭassini is not equipped to answer that question, but NASA's Europa Mission, due to launch in the 2020s, will be another step in the right direction.īacteria appears to be growing on these bright yellow sulfide deposits on Endeavour Ridge. These living systems are in total darkness, using chemosynthesis instead of photosynthesis as an energy source. Warm water, heated by the Earth, oozes out of cracks carrying hydrogen sulfide, minerals and nutrients, which nourish bacteria and a whole food chain of creatures that thrive around the vents. You can see hydrothermal vents in action through Canada's unique Neptune Project, off the coast of British Columbia, which involves a series of cameras permanently installed on the ocean floor. On this pass by Cassini, the scientists are hoping to find hydrogen, which could have come from hydrothermal vents on the floor of the moon's ocean, similar to those found in the deep oceans on Earth. Drink a lot of beer and you will see for yourself. That doesn't prove there's life, but organic chemicals like methane can be produced by life. ((JPL/NASA/AP))On previous flybys, the spacecraft detected water as expected, but also methane and carbon dioxide, which are chemicals involved in life. The Cassini spacecraft passed just 26 kilometers from the surface. The surface of Enceladus, captured Cassini's previous close encounter with the moon in 2008. Instead, it forms a hazy ring around Saturn, outside the main rings.That means if you were standing on the surface of Enceladus beside one of these fissures, you would see snow falling up.Ĭassini has flown through these plumes before, the first time in 2008, but this week's encounter was the closest - only 50 km above the surface. That makes the gravity on its surface very low, so most of the material that blows out of the cracks in the ice does not fall back down. Water from below works its way through the fissures to the surface, where it blows out into space, instantly freezing into icy plumes.Įnceladus is only about 500 km across, so it would easily fit between Toronto and Montreal. That presents a considerable challenge just getting to those oceans.įortunately, Enceladus has provided an opportunity for us to sample its ocean through long deep fissures in the ice, called tiger stripes, that run along the moon's south pole. The problem with finding life on - or rather, in - these moons is that the ice is very thick, perhaps hundreds of kilometres deep. ![]() This week Cassini has put its focus on the moon Enceladus, which is known to have liquid oceans beneath its surface. An artist's conception of the Cassini probe against Saturn's moon Rhea. ![]()
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