Instant communication was so dumb...
Such a stupid way of portraying communication process between the mission control and the spaceship. One of the fundamental problems with space travel is that the further you go, harder it gets to communicate. The speed of light is finite and radio waves travel at that speed (about 300,000 km/s). In other words, when you send a message to the spacecraft away from earth by about a couple of light minutes, it takes a couple of minutes to reach it and the same time vise versa.
The distance between Earth and Mars varies between 55 million kilometers and 400 million kilometers. To put it in the light minutes, it varies between 3 and 22 light minutes.
In the movie you can witness how William D. Stanaforth (Mark Strong)has instantaneous video calls and chatting back and forth with the mission control back on Earth even about at the halfway point of his journey (which would've been impossible). It turned me off so bad and was such an easy thing to fix that I can't just suspend my disbelief and give a pass. Unfortunately, that's not my only issue with the movie...