Man Plus
Frederik Pohl
 In the not-too-distant future, a cold war threatens to turn hot. Colonization of Mars seems to be mankind's only hope of surviving certain Armageddon. To facilitate this, the American government begins a cyborg program to create a being capable of surviving the harsh Martian environment: Man Plus. After the death of the first candidate, due to the project supervisors forgetting to enhance his brain's ability to process sensory input to cope with the new stimuli he is receiving, Roger Torraway becomes the heart of the program. In order to survive in the thin Martian atmosphere, Roger Torraway's body must be replaced with an artificial one. At every step he becomes more and more disconnected from humanity, unable to feel things in his new body. It is only after arriving on Mars that his new body begins to make sense to him. It is perfectly adapted to this new world, and thus he becomes perfectly separated from his old world, and from humanity. The success of the Martian mission spurs similar cyborg programs in other spacefaring nations. It is revealed that the computer networks of Earth have become sentient, and that ensuring humanity's survival will guarantee theirs as well. In the end, the network is puzzled...it appears that something else was behind the push to space, a mystery even to the machines.