Sorry to ruin your enjoyment of Mission to Mars—or, fine, Aliens and Star Wars—but it joins a host of sci-fi movies that just can't quite get their space science right. Here are the most common offenses and offenders.
You'll note that The Right Stuff and Apollo 13, the two movies that are based on actual events, come off clean. Everyone else? Fast and loose with physics! But if you thought the most unbelievable part of Armageddon was that there was sound in space, well, maybe you just know more about asteroid drilling than I do. [io9]