Mark Watney's Explosion Scene

Mark Watney is stuck in space, on Mars. His crew mates left him thinking he was dead and to make the best of the situation, he made a plan and figured out how he could make it back home. Mark plans on surviving until the next mission, Ares 4, so they can take him back to Earth. He calculates the calories he needs each day and how long his food will last him. He concluded that his food won't last until the Ares 4 mission so he decides to plant and grow food. Mark is a botanist so he knew what to do, including using human feces as the fertilizer for the soil.