The actors, the music, the scenario, and the execution were great from the beginning to the end. The only problem is that it showed how little research was done to get the ideas of the movie sound logical. I know it is science fiction, but many aspects should be as close to scientific as possible. Sorry, spoiler alert here: to imagine a trip to Mars with this little preparation and a crew this incompetent is unbelievable. Plus, the tether cable idea although fixes the gravity issue, is crazy to think the engineers didn't imagine a better idea to get to the other side other than climbing, from the top of my head I can imagine 5 or 6 ideas where a motorized way to go the other side of the tether could be used. Anyway, great execution, but hated the stupidity of the challenges they faced. I am sure I am going to hear much from those stating this is art, and it is not supposed to be all true, and it is the feelings and resolution and the humanity of the story. And they are right, but this doesn't mean we have to settle for scenarios where the people sending this ship to mars didn't think it through.
I also needed to point out that to have good gravity, the entire mechanism between the ship and the other end of the tether must be balanced, meaning the weight of the entire moving mechanism is double the weight of the ship, that alone means they must use double the energy to keep this spinning wheel from hell hurdling towards Mars with some resemblance of control. Not to forget the weight of the tether cable itself. If I had to decide, I would leave the ship they came in attached and replace the weight of the tether with enough storage of oxygen tanks or, better yet, enough replacement parts for the life support systems on board.
The 3 stars they get here is purely for the appreciation I have for the other ideas and more importantly the cast and their flawless executions.