Shortly after arriving on Mars, the Ares 3 mission was forced to evacuate due to a severe dust storm threatening to tip over the ascent vehicle, their only way off Mars. As the astronauts worked their was from the Hab (the habitation module) to the rocket, the communications antenna was torn loose and punctured Mark Watney’s suit. The other crew, not being being to find him, noting that his suit was radioing zero life signs, and that the rocket was very close to tipping over, they left Watney, presumed dead, on Mars.
He was not dead, though. He fell in such a way that his suit closed most of the leak, and the atmosphere systems were able to compensate most of the way. When he woke up, he used his patch kit to patch his suit and went back to the abandoned Hab. Ares 4 would be coming in about four years, and to Schiaparelli Crater some 3200 km to the southeast. The Hab was designed for six people, provisioned for up to fifty-six days, which meant he had plenty of excess CO2 extraction capability, and food for one person for about a year. NASA had also sent up a few actual potatoes to be used in making a meal for the Thanksgiving holiday. He had some soil for experiments, so he started covering the floor with Mars dust, and letting the bacteria from the soil colonize it.
The only problem was that Martian soil is dry, and he did not have a source of water. The ascent vehicle was sent to Mars years prior to the mission so that its generator could slowly suck CO2 out of the air to be used to create hydrogen for the ascent. The Hab had facilities to recycle CO2 into O2, which is half of water. He could turn the unused hydrazine from the descent vehicle into its constituent hydrogen and nitrogen molecules, and then burn the hydrogen. This seemed to work, except that he neglected to consider that his setup leaked hydrogen. This resulted in some burned hydrogen, but a lot of unburned hydrogen and oxygen, a rather explosive mixture. So he slept outside in the rover while he considered what to do. The solution was to wear his space suit inside, trick the Hab into taking most of the oxygen out of the air and burn the resulting hydrogen.
Meanwhile, Mindy Park was fulfilling a satellite picture request of the site when she noticed anomalies in the equipment and notified the head of NASA, which then began thinking of how to alter Ares 4 to rescue Watney. Watney, on the other hand, started to modify one of the two rovers for long-distance travel, so that could make it to Schiaparelli Crater . The difficulty was getting enough power to actually be able to travel far. He attached the battery from the second rover to the first one by making makeshift saddlebags, putting the battery on one side and an equal amount of rocks on the other, then strapped on stacks of solar panels to the top. After a short test, he realized that it got too cold unless he used the heaters (Mars is generally -60° C), which drained power. So he recovered the RTG that powered the ascent vehicle’s fuel creation system, a plutonium-powered electricity generator that works by getting really hot. He tore out the insulation from the rover, put the RTG inside, and tested it out by driving around nearby the Hab for a day. Then he set off for a twenty day trip to test the system and also achieve another goal.
NASA, which had been watching him every day via satellite, noticed that he had set off in the rover, but not towards Schiaparelli. They plotted his course and, in a flash of inspiration, decided that he was going to recover the Pathfinder lander in an attempt to communicate. Since the Hab’s communications antenna had blown off, he had no way of communicating with Earth. Pathfinder, if it still worked all these years later, did have the ability. Sure enough, that was his target, which he recovered and returned to the Hab. NASA, having predicted this, had been spending sleepless nights getting the Pathfinder computers up and running to get its signal. After he connected it to the Hab’s power supply (its own batteries were long dead), it booted up, sent a signal, which Earth heard, and sent an operating system update to tell it where to point its antenna). Watney noticed this, and wrote a message on a card where the camera could see it. Initial communications was by him writing messages on a card and them rotating the camera to sixteen different positions (0 - F) to send ASCII characters. Since the lander also communicated with a small rover, NASA uploaded an operating system update that sent a signal on the rover’s communication frequency, then had him patch the rover software to receive it.
Some time later, the fabric in the airlock he was using gave way, leading to an explosive rush of air that tore open a big hole in the fabric that made the Hab, and caused a leak in his suit. After some panicked action to save himself, some thinking in the rover, he was able to get a proper suit from the Hab and then patch it up. Unfortunately, the accident killed all the bacteria in the soil due to the cold, which meant that he would never be able to grow anything in it again. He was almost ready to harvest his potatoes, so the timing was good, but it meant that he could not hold out until the supply mission that NASA was planning to send.
The main problem was that, due to the poor positioning of Earth and Mars, sending a probe in time would take a lot of energy and would need to be hastily built. NASA repurposed a rocket from a Saturn mission with a simple supply probe filled with protein cubes, but vibrations during takeoff unexpectedly liquified the cubes and the liquid sloshing around destabilized the rocket, leading to catastrophic failure. The only other option appeared to be building an even hastier probe that would crash-land on Mars, launched from a Chinese rocket. There was another option, computed by one of the trajectory engineers during his vacation that would let the Hermes, the craft taking astronauts from Earth orbit to Mars orbit and back, swing by Earth with a gravity assist, pick up a resupply from the Chinese rocket, do a Mars flyby, where it would remotely pilot the Ares 4 ascent vehicle into an intersecting orbit and grab Watney. Neither had high chances of success. The head of NASA decided to send the crash landing probe, which nobody really believed would succeed in landing usable food, but only risked one life instead of the six that would be risked under the new trajectory. One of the NASA administrators under him covertly sent the trajectory to the Hermes. The crew chose to disobey orders, hack the computer to not receive course corrections from Earth, and entered the “Rich Purnell trajectory.”
This forced NASA’s hand, so they launched on the Chinese rocket (obtained by promising a Chinese astronaut would be on Ares 5), which successfully resupplied the Hermes. NASA then began instructions for modifying the second rover to become a trailer carrying the supplies to get Watney to Schiaparelli Crater. The first procedure involved drilling holes in the rover with the rock drill, which Watney connected to the Hab supply. Unfortunately, due to the grounding circuitry of Pathfinder and the fact that his workbench (on which Pathfinder sat) was metal, meant that when he leaned his drill against the workbench a large amount of current went through Pathfinder, frying its circuitry, which meant that communication was only one way. Watney would spell out messages to NASA in Morse code using rocks, which they could read with the satellite pictures. He was on his own for rover modifications.
Watney pretty much tore everything out of the second rover and made it into a trailer for the first. He put in the O2 reclaimer, the CO2/O2 level adjuster in the trailer, along with some water and other items. He put the RTG in a bag of water and bubbled the return gas from the CO2/O2 adjust through the water to heat it up from Mars nominal temperature. He also used the two emergency tents to create a big room where he could escape from the cramped rover, which had him going nearly crazy during the shorter trip to get Pathfinder.
He got everything set up in time to drive out to Schiaparelli. Although it was supposed to take him about 45 sols (Martian days) to get there, he set out 100 sols before the rendezvous date to give himself some extra time in case something went wrong, as well as time to modify the ascent vehicle to lower its weight to achieve the higher orbit he needed. NASA and Hermes were aware that a dust storm was in the middle of the area he needed to drive through, which posed a substantial danger to him. Since the dust storm was fairly gradual, Watney would be in the middle of it before he realized it, and then he would not have enough solar power for life support, let alone to charge the batteries for travel. However, Watney noticed that the solar cells were outputting slightly less power, noticed that the sky was a lot clearer one direction than another, and realized he was entering a dust storm. He waited for a day to see the change in output to determine which way it was moving. The he drove half a day south, left a solar cell and logger, did the same the next day, then went back and collected them. This way he knew that the storm was to the north of him and that he should drive south.
He arrived safely at the edge of Schiaparelli, but needed to get down into the crater. He went down a sandy ramp that his map had identified, but partway down the sand became unexpectedly loose, causing the rovers to tip over. Fortunately, nothing was damaged and he only had to figure out how to right the rovers. He drove slowly down the ramp after that. A few days later he had arrived at the Ares 4 ascent vehicle and contacted NASA, who gave him instructions on what was pretty much a gutting of the rocket.
The day arrived, and Hermes remotely controlled the launch. Naturally, the launch did not go perfectly, leaving Watney in a trajectory close to intercept, but not quite. Hermes had to vent an airlock (not an easy task with the safety measures), and one of his crew members did a tethered retrieval. He was safely aboard, rescued by his crew members after two years on Mars. And boy did need a bath.
The Martian is a great Robinson Crusoe on Mars story. The story is told mostly through Watney’s logs to posterity (if he did not make it), with occasional narratives concerning NASA or the crew on the Hermes’ actions. The logs are often better than the narratives, and they definitely make Watney’s personality very vivid. I wish that the language had less profanity and sexual content, though. I get that he supposed to be a “real guy” but it really does not add anything and the “folksy” effect could be accomplished in other, more elegant, ways. A bigger complaint is the rebellion-saves-the-day trope that seems near universal in current American movies. Inevitably the protagonist must disobey orders and make a risky move in order to succeed. I get that it is a story, and I get that much of the 16 - 40 age group has problems with authority, but it is getting pretty old, and is just not believable. In real life risky disobedience often ends in sorrow. I expected better of a book.
Weir has done an excellent job in bringing Mars to life, in a way similar that Kim Stanley Robinson does in the Red Mars series. The logs are very detailed—Weir clearly did a lot of research and calculations in order to write this book—and you can almost see yourself surviving on Mars. This is a very technical book, although Weir has made the details accessible to a layman. Readers wanting witty repartee will be disappointing, but if you have ever wondered “I wonder if I could live on Mars?”, as I think many have, then this is the book for you.