UK folks, Duncan Jones' "Moon" is on iPlayer! Brilliant piece of atmospheric science fiction that, unlike some, actually has a really good storyline too. https://www.bbc.co.uk/iplayer/episode/b01js1rs/moon
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When I watched it, I got mightily confused near the end: I couldn't imagine why the guy is trying to commit suicide (I think something earlier in the movie implied that the accelerations of the cargo railgun were too high for humans).
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@_thegeoff Hmm... I thought the ending claimed that the clone that returned lived for some time on Earth.
Also, expose to whom? The people who operate the Earth end of the operation and thus can probably tell that no new engineers are being sent up? But yes, I didn't consider this option, and the people dealing with helium shipments need not have been in on the whole thing.
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@robryk At the same time....maybe nobody actually cares as long as stuff is cheap? Been a long time since I've seen it, tomorrow isn't a school night so it's getting cued up :)