Short one this time. Basically the ISS can't take the lack of updates and patching for XP (which they were using), and decided to go for Debian for the for-astronaut-use laptops that go up and back and some of the ones that hang out there. This seems to be because they've gotten worms and such in the past (since they get users and data from all over), and Linux being inherently more secure in practical use (and way more quickly patched) means less time spent worry about their machines and more time spent tossing legos back and forth in microgravity with one hand while figuring out how to solve the testicular cancer boson unification theorem with the other.
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