In The Martian, why does Mark have to move to the Schiaparelli Crater? How does he get there, and what is the problem with that?
Mark has to move to the Schiaparelli Crater because it is the landing site of the next planned mission to Mars, and it has the required rocket vehicle to get him into orbit to be rescued. The rocket is placed there by Nasa in advance of the next mission.
He gets there in a modified rover vehicle. He modifies it primarily to make it able to travel further on one battery charge. Amongst other things, the modifications he makes are:
- Disconnecting the electric heating for the cabin
- Putting a small nuclear-isotope power generator in the cabin to provide the heat he needs to survive.
- It carries a bunch of solar panels from the base.
- He makes a hole in the cabin roof to create an storage bubble. For the longer journey he needs more space to store equipment and consumables like food and water.
(Many of these modifications he makes earlier in the movie, before he goes to find the Pathfinder probe)
He travels largely at night, and sleeps during the day while the battery recharges.
Apart from the technical challenges to modify the vehicle to live in for his journey, he encounters no problems in the movie. In the book he encounters many more life threatening problems.