Here is a good time to yield the statutory spoiler warning. But don't let that dissuade you from reading the remainder of the article—it may save you a few bucks at the movies.
I admit to holding many gripes with this standard-issue Hollywood blockbuster: basic laws of physics are optional; realism applies except when sound travels through space; an accomplished writer has never written about herself; Lawrence Fishburne appears only to give the protagonists access to the engine rooms, then dies; a spacesuit protects Chris from a fusion (or fission?) reactor's radioactive exhaust; and love magic saves the day (more on this later). But perhaps the worst crime this movie makes is that it insists on a happy ending where none was due.