In Approaching the Unknown, William D. Stanaforth is a brave man, so much that he has dared to take a step that can be very important for humanity, as it is to go to Mars alone, to discover the planet Red for the people.
The trip is dangerous and he knows it, but he is not prepared to die, even though we are not one. That is why preparations have been made so that William can return safely, bearing in mind that there may be unforeseen events.
These unforeseen occurrences soon, when the life-support system, which keeps William alive, begins to fail, threatening his life and making William’s priorities change.
Before he wanted to reach Mars, but now he wants to be able to stay alive and try to return to Earth, because that is his only chance of survival, which is impossible in space.