Sure, I have studied these things a couple of decades ago. Now that I read my comment above I realize it was badly worded. I didn't mean to say all heat would

Sure, I have studied these things a couple of decades ago. Now that I read my comment above I realize it was badly worded. I didn't mean to say all heat would simply be radiated without posing a problem. I meant that the only way for a body to lose energy in space is by radiation (without ejecting matter, I suppose).