A space movie isn't a space movie without the science nerds trying to rip it apart for errors.
Below you can check out James Gunn's response regarding a specific scene that happened in Guardians of the Galaxy between Star-Lord and Gamora.
Via James Gunn Facebook:
Hello fellow nerds.
Sometimes people's incorrect beliefs about science gained from past works of fiction - such as that a person will explode in outer space without a spacesuit - can often make them believe the correct science within another work of fiction is inaccurate. This is just a little about the science of Guardians of the Galaxy, which has been much debated.
There are minor SPOILERS TO FOLLOW, as well as in the attached article, so be wary...
Firstly, BadAsss Digest is right in the following article, I was making first and foremost a space fantasy or space opera, a pulp film, and that fun trumps everything. That said I wanted to make sure the film was as scientifically accurate as it could be. So I consulted with a NASA scientist throughout the film. One of my questions was whether Peter Quill could survive in outer space without a spacesuit, and without the top of his head and hands covered. The answer is yes, for a short amount of time, if he had oxygen. And, without a mask, if he released all oxygen from his lungs, for a significantly shorter amount of time.
Throughout test screenings, people would be upset when Quill saves Gamora and both of them survive in space for a short amount of time without space suits or oxygen. But I had to stick to my guns in the editing of the film, as it was completely possible. In addition to the reasons the article states, there are a few more why Quill and Gamora survive -
-Gamora is genetically and cybernetically enhanced, allowing her to stay alive longer than Quill would.
-When Quill is in outer space outside both the Kyln and Knowhere, there is no anti-gravity, but there is residual atmosphere from those places. Rocket even mentions it to Quill outside Knowhere. This lessens the impact of space.
-Much of the scene is shot in slow motion, meaning it takes up more time on screen than it would in real life.
-The airlock within the Eclector (Yondu's ship) has regenerative properties, which is why both Quill and Gamora are all good when they are pulled into the ship. After all, the Ravagers are a bunch of thrill-seeking idiots. One of Kraglin's favorite pastimes is probably jumping out into outer space completely nude for a few seconds and quickly clamoring back in.
EDIT - MORE QUESTIONS ANSWERED -
How does Quill get batteries for his Walkman?
This one I don't get at all. They've mastered anti-gravity. I think they can figure out a power source for his Walkman.
How does everyone speak English?
They don't. In the mug shot sequence, you'll see that Quill has a translator in his neck.
I also have reasons for why the Milano and other vehicles are able to travel between planets at such fast speeds, but I'll probably save that for later on. [smiley face]