Sol 25. Watney does some calculations. He needs 1387 sols, or 1425 days, of food. To survive until Ares 4 lands, he needs to eat 1500 calories per day. If he covers the entire floor of the Hab, the 5 unused bunks, and the emergency pop-tents from the rovers with soil, he’ll have 126 square meters of farmable land. With this, he can grow about 850 calories of food per day. At this level of sustenance, he’ll starve, but survive. But to make this work, he needs another 250 liters of water more than he has. 10000
Watney’s calculations highlight the desperation of his situation. While his plan to grow crops was a breakthrough, he’ll grow, at most, enough to barely sustain himself until the Ares 4 landing. And at present, he doesn’t have enough water to do this. This unsolved problem builds suspense.
Sol 26. Watney continues bringing Martian soil into the Hab to grow his supply of crop soil, and starts his seed crop of potatoes. Watney explains that NASA sent twelve whole potatoes so that the crew could make and eat a “Thanksgiving dinner” together on Mars. He cuts them up, plants them, and raises the temperature in the Hab so they’ll grow faster. 10100
Looking for something to kill time, Watney finds Commander Lewis’ data-stick, and discovers she brought many seasons of dated TV shows. He decides to watch Three’s Company. 00100
Watney mocks Lewis’ taste in TV but he watches the show anyway—like music, TV is a way to pass time and stay connected to other humans.
Sol 29. Watney still has no source of water, but works on setting up the pop-tents (emergency shelters attached to the rovers) and preparing them to become farmable land. Watney attaches the pop-tents’ air lines to the Hab so that the air-levels in the pop-tents will remain stable, then he moves arable soil into the pop-tents. The day’s work done, he watches another episode of Three’s Company. 10100
Even though Watney’s plan is incomplete without water, he continues to work towards his goal of planting a large crop of potatoes. The pop-tents were intended for a different kind of emergency, but they are still helping Watney survive in an emergency situation.
Sol 30. Watney decides he’s going to make water from hydrogen and oxygen (an incredibly dangerous thing to do). Due to this, Watney will use the Hab’s oxygenator to convert carbon dioxide from the MAV’s fuel plant into oxygen. All he needs is hydrogen. Because the pilot of the Ares 3 mission, Martinez, made a smooth landing with the MDV, he didn’t use all of the hydrazine fuel that was on board. Watney plans to turn the hydrazine into nitrogen and hydrogen (plus a bit of ammonia). This is a reaction that generates a lot of heat, so Watney will have to be careful not to cause an explosion. Watney glibly proclaims that he can’t wait to watch the next episode of Three’s Company. 10110
Watney has developed a creative solution to the problem of not having enough water. Yet, ironically, the only way Watney can avoid death by starvation is to make water through a process that easily could kill him. Watney’s ongoing references to Three’s Company read as jokes that he has written in for the log-reader’s benefit. We can also read these jokes as a coping mechanism—rather than betray the fact that he is worried his next experiment could kill him, Watney makes a joke about TV.