Thanks guys. I see that I wasn't wrong in my assumption.
Funnily enough, around here people don't bring
Prometheus that often when Hard SF is discussed.
Second, Christopher Brady's definition of "science fantasy" is not the way that term is used in the real world. In the real world, science fantasy refers to works which feature world-building speculations based on both science/technology and also on magic/supernatural. Star Wars isn't science fantasy because George Lucas didn't explain how hyperdrives work; it's science fantasy because there are space wizards wielding a mystical force which permeates the entire galaxy.
This might sound kind of awkward, but what do you mean exactly by "explain"? I mean, come to think about it, movies rarely truly explain future-tech. There's not much to explain in
Gravity or
The Martian, because there's not much of future-tech.
But, consider
2001: A Space Odyssey often cited as hard SF movie. Kubrick didn't really took any time to explain anything and there was sort of cryosleep, pilots using what seems to be
tablets, such things. On the other hand
Event Horizon: not very good example of hard SF, but one of central characters, Dr. Weir, puts on the mantle of Mr. Exposition, explains the concept of FTL travel, black-hole based drive... while in reality explaining nothing. It's just a bunch of words, that are supposed to see like an explanation, but at the end of day we still don't know how it's possible that people managed to create an artificial black hole.
So, what's your opinion on this topic?