 It is recording Professor David Rothery We meet again. We do indeed. What are you excited about right now? Well, remember what's exercising me is the prospect exercising you Apart from my boss I'm exercised by the prospects of life underneath the surfaces of various icy moons in the solar system How many icy moons do we have? Oh, 60 or so decent sized ones, but not very many that might have life They're extremely cold at the surface of what it wouldn't be made of ice But some of them underneath we think it's warm enough for the ice to be melted. So it's water So you've got a water environment by definition above zero centigrade. That's warm enough for life You just need a way to provide nutrients so creatures can find sustenance now on earth The life that we're familiar with relies on sunlight, but there are places in deep oceans Where there's no sunlight, but there's a whole ecosystem based on chemical rich water That's been mixed in with the rock below the ocean floor and it seeps out through hot vents rich in chemicals and There are organisms which make a living out of getting involved in the chemical processes So that's chemo synthetic life rather than photosynthetic life light that builds itself up based on chemistry And this can happen where you've got below the surface of an icy moon You've got a layer of water and then some rock to provide some chemicals and that's where things could live Occasionally see this being discussed both online and on the news and a lot of it to me seems like kind of speculation but with a lot of Maths and science obviously to back it up. How do we know without actually sending probes to some of these places? Oh, we don't know whether there is life there without sending probes But we know that the conditions that would suit life are probably there Because we can tell that the ice isn't solid all the way down. There are reasons to expect that it's molten There are ways of providing heat to the inside which is why not all icy moons have got oceans underneath But many of them have if there's a heat source So we've got the right conditions for life You've been have to ask yourselves well if we have the right conditions, how could life get in there in the first place? Well, I've reached a ride on a meteorite from the earth to one of these unlikely or it started there On its own accord or else it doesn't exist But could life start there? Well, yes because we think life on earth is most likely to have started at hot vents Hydrofiber vents on the ocean floors. If that's how life started on the earth It could start anywhere else where similar conditions exist. So we've got to go and find out. I want to know Do you think in your lifetime you will be in the know? There are going to be missions to Europa and hopefully even better ones to Enceladus Nice moon of Saturn is jetting stuff out to space What we've got to do is fly through that jet of water that's come from below the icy crust with the right analytical instruments And you can see if any biological processes has been going on. We could be there in 20 years finding that out 20 years. Yeah, it'll be robots. It'll be robots. We won't send people for a while But one day Thank you for sharing your excitement. You're welcome Oh, I should do that