When you are only about ninety degrees from absolute zero, it is not hot, despite the fact that the sun is shining down on you twenty-four hours a day. The answer to this riddle is that you are on Uranus, in the arctic circle, where the sun is a bright star almost directly overhead. And what are you doing on Uranus? You need the money. Nils Borgmann, however, was sweating. And the reason was that the heating unit on his space suit, like the heating units on almost all space suits, was not functi