7 Happy Movie Endings That Are Totally Ruined By Science

5. The Martian: Watney Probably Got Cancer

Sand storms and exposure to the vacuum of space aside, one of the major dangers facing Mark Watney during his time on Mars would have been completely invisible.

Turns out that there's alot of radiation flying around in space. Down here on Earth, we're fairly well protected by the magnetosphere, which deflects most of the dangerous stuff. However, once you leave the protective bosom of the Earth's magnetic field, you open yourself up to serious damage.

Ionizing radiation is measured insieverts. Onesievert is generally associated with a 5.5% increase in in the risk of developing fatal cancer; on Earth we're exposed to0.00001 sieverts of daily background radiation, Mars, however, with its thin atmosphere and no magnetic field, could expose astronauts to a 0.66 daily dose. The equivalent of a weekly full-body CT scan.

This is not even taking into account the exposure endured during the trips to and from Mars through open space, where the dosage ishigher still- a factor that should have been taken into account by the crew when planning their heroic rescue mission.

So, that lovely, heart-warming ending in The Martian that shows Mark Watney living a nice, normal life after his ordeal?Probs not.