...Marooned is a good movie.
If you're inclined to consider when it was made, or you're old enough to remember when the idea of manned space exploration was actually exciting, you might even think it's great. The worst thing I can say is that it's certainly not fast-paced: if you're looking for a sci-fi action spectacular, this probably isn't going to be your cup of tea.
The specifics are covered very well in previous users' comments (and in Roger Ebert's ***/**** review), so I won't repeat them here.
There is one thing I'd like to clarify, though, if I may:
Anyone looking at the user ratings and user comments should take into consideration that a (very) abbreviated version of this movie was shown on Mystery Science Theatre 3000 as "Space Travelers." I'm a pretty hardcore MST fan myself, and I agree that it was a funny episode. However, there's a certain type of MSTie that finds it entertaining to visit the IMDb and "vote" (negatively, of course) for the movies featured in their favourite episodes, with a view to knocking them down into the IMDb's "Bottom 100" list. Sometimes this is reasonably well-deserved: honestly, some of the worst (best) movies featured on MST3K would be indefensible in any form. Other times, particularly when the original is cut to pieces (this one lost approximately 1:15 of its 2:15 running time, while "gaining" some lousy incidental music and a shabby new title sequence*), I don't think it's right at all.
If you want to watch an interesting, thought-provoking sci-fi drama, "Marooned" is a good bet. If you want to watch a funny episode of MST3K, "Space Travelers" (#0401) is an equally good bet. You can even watch and enjoy both, as I have. Don't let the strange mix of votes and comments here dissuade you from watching it entirely, though, because that would be a mistake.
(A minor mistake, admittedly, but still -- a mistake.)
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* Credit where it's due: most of this hack job was courtesy of re-distributor Film Ventures International, and not the folks at MST3K. If you come across a non-MST'd version of this movie that runs about 1:30, don't waste your time: I guarantee it'll be neither interesting _or_ funny.
