I saw The Martian in English without subtitles and English isn't my first language (saw the film, didn't read the book), but I was wondering why the space station on Mars didn't already have the kind of messaging system that is later on used mid-way through the movie.
Is there a good reason for this explained in the film that I just didn't get?
It did. Unfortunately, it all either broke during the dust storm which cause the whole situation (Mark's injury was caused by the satellite dish which the storm carried away), OR the backups that were supposed to use the MAV return module (which the rest of the crew used to escape to Hermes).
This is covered in the Andy Weir's book that the movie was based on:
I knew it was hopeless, but I tried firing up the communications array. No signal, of course. The primary satellite dish had broken off, remember? And it took the reception antennae with it. The Hab had secondary and tertiary communications systems, but they were both just for talking to the MAV, which would use its much more powerful systems to relay to Hermes. Thing is, that only works if the MAV is still around.
I had no way to talk to Hermes. In time, I could locate the dish out on the surface, but it would take weeks for me to rig up any repairs, and that would be too late. In an abort, Hermes would leave orbit within twenty-four hours. The orbital dynamics made the trip safer and shorter the earlier you left, so why wait? (LOG ENTRY: SOL 6)
