The fall of George Clooney is absolutely not realistic, there is no technical reason why he should fall away. Other blog's published a complete list of "big errors": locally some effect is realistic but the general picture is impossible (the several space stations involved in the movie move at a relative speed of several kilometers/sec, a satellite or a space station takes several days to fall down from the height of several hundreds kilometers, etc.). Anyway what really I could not stand were the poor story, the silly dialogs, the pleonastic and exaggerated recitation: it is a bad film, technics apart. The scene of Sandra Bullock on the lake shore, at the end of the film, reminded me the dying soldier/Peter Sellers with the trumpet in Hollywood Party (PS: she was not dying).