After I go to a movie theater I usually look up the film I just saw through imdb.com (Internet Movie Data Base). So after watching The Martian I did just that. For each movie there might be pages for memorable quotes from the movie (or at least what imdb participants think are memorable), trivia, crazy credits (unusual things that go on during the closing credits or mentioned in the credits), and goofs.
The goofs page lists everything eagle-eye viewers catch, such as being able to see the camera in the faceplate of the environmental suit or airplane contrails in the sky over Mars. There are also continuity errors (a well known one from another unnamed movie – we see a man with the top two buttons of his shirt are open, a moment later the shirt is buttoned to the top, a moment after that the top two are open again), factual errors, and plot holes.
I find this list fascinating, partly because I rarely spot the problem when I'm watching the movie.
Alas, The Martian had 32 goofs, a couple of them rather major. The first one is a factual error. During the movie one of the airlocks malfunctions and rips away from the habitat. We see our hero secure a sheet of plastic over the opening to the habitat and strengthen it with duct tape. The plastic then flutters in the breeze. But that will never work, the air pressure difference between the interior of the habitat (where our hero takes his helmet off) and the Martian atmosphere is too huge. A plastic sheet like this would pop immediately. And even if it did hold Martian air isn't strong enough to make it flutter.
This particular incident was handled correctly in the book. A seam in the habitat itself blew and our hero carefully cut away part of the hab material from one area (making the hab smaller) to fill and thoroughly seal the hole.
As for the other big error, a hole in the plot... Many scenarios of missions to Mars send an unoccupied return rocket ahead of the crew. While waiting for the crew to arrive it can do various extraction operations to create fuel for the return to earth. The mission shown in the movie is the third. The return rocket for the fourth mission is already on Mars though quite a ways from the site of the third mission. It is this rocket that our hero uses to leave Mars. But the movie begins with a strong dust storm. Our hero is stranded when the rest of the team is in a hurry to launch the return rocket. The hurry is because the wind is about to tip the rocket over, which would strand the entire crew.
So why didn't the fourth return rocket not tip over? Surely, there were storms with strong winds there as well.
As I said in the earlier post, this storm is in the book and the author already admitted the thin atmosphere could not cause the rocket to tip over, no matter how fast its winds.
Even so, I still recommend the movie.