Originally Posted by cherokeesam
I dunno, but its appearance in Thor 1 was very bizarre. Some people say that it's shown to be on a planet, but it's not: it's the center of a freaking galaxy/star cluster. It defies all (known) laws of astrophysics.
It's a big magic rock floating in space/another dimension. Just like the comics. They don't need to explain everything, especially if they're going to try and retain the vagueness of the "Magic or super science?" theme.