Worth mentioning that, at a minimum, he is an astronaut specifically chosen and psychologically trained and prepared for a multi-year to mission to Mars. He sho

Worth mentioning that, at a minimum, he is an astronaut specifically chosen and psychologically trained and prepared for a multi-year to mission to Mars. He shouldn't have normal human reactions and given that his situation never turns truly hopeless, he has been trained to keep working the mission as well as he can. Also, though he is isolated, he knows everything he does and discovers will be eventually found, analyzed and made useful by NASA and future space travellers. All of this can provide a sense of greater social connection that can keep him motivated to keep going.