If you are the slightest bit inclined to see Europa Report, which has just come out on DVD this week in the U.S., try to see it before you watch Gravity. Like the newer film, it works hard to depict astronauts in a realistic fashion-- in certain ways, its astronauts behave more believably than Gravity's-- making very good use of its limited budget.
Europa Report is a decent hard-SF found-footage film that is considerably better than I'd expected. It deserves to be appreciated on its own merits.
If you watch the big-budget major-studio special-effects extravaganza first, your appreciation of the small-budget independent film may well be threatened. Already Gravity's box-office receipts have surpassed those of Europa Report by a factor of more than eight hundred.
ER is a noble attempt to make a hard-science-fiction "space suit film." If at all possible, it should be an appetizer to Gravity's feast. See it first.