Simplified scenario for manned Mars missions

We propose a simplified but efficient scenario for a manned Mars mission. The idea is to select a crew of only 2 astronauts and to bring in situ resource utilization systems in the same vehicle. For security reasons, we suggest duplicating the mission as it was proposed by Von Braun. At very moment of the journey, the two vehicles would stay close so that each crew could provide help to the other. We show that this scenario is much simpler than the last design reference architecture proposed by NASA. The initial mass in low Earth orbit is minimized and the risks are also reduced. The total cost could be in the order of 40 billion dollars.