But with his space suit, Watney can walk around on Mars relatively ... SCIENCE FICTION: With only limited food, Mark Watney in "The Martian" grows potatoes to save himself from starving.

In "The Martian," astronaut Mark Watney is screwed. He's alone on Mars after surviving a horrific dust storm. In addition to a limited supply of food and water, Watney has no idea how he's going ...