What I heard from books or other materials is that the heat is nothing but a sum of movements of molecules. So, as you all know, one common myth breaker was like "Unlike movies, you don't get frozen right away when you got thrown out to the space". But the thing which bugs me is that things in the Universe, eventually cool off, and how is that possible, when there's no other things around, to which the molecules transfer their heat?

What I've heard from books and other materials is that heat is nothing but the sum of the movement of molecules. So, as you all know, one common myth breaker was "Unlike in movies, you don't get frozen right away when you get thrown into space". 

But the thing that bugs me is that things in the universe eventually cool down. How is that possible when there are no other things around to which the molecules can transfer their heat?