Submarine missions on other planets

So most of you have most likely heard about the resent discovery of an underground lake on Mars. That is incredible news because water is an element that has to present for life as we know it to be present. But how do we explore this lake? It is not like the rovers we have on mars know are able to put on their swimming suit and search for life. What we need is a submarine, and luckily plans to make a submarine to explore a water body on another planet has already been talked about. The plans and talks was regarding the exploration of Jupiters moon Europa. The plans have varied a little as far as i can tell, but first the submarine would need to get through the big ice sheet. This could be done by heating up some part of the aircraft to melt its way down to the underground lake. Then once it got down there it would have to be powered someway somehow, but a solution to this could be a nuclear powerplant, as solarpanels will not help much, as there is no sunlight down there. I can imagine that some of the problems regarding to exploring Europas ocean would be the same when trying to explore Mars's underground lake. Who knows maybe the lake on Mars might be the perfect fit to test the technology and and practice it? I have to say i hope they come up with a plan to explore it ASAP.

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