Salotti_2011abstr

Copyright © 2011 by Jean Marc Salotti. Published by the Mars Society with permission.

 

Manned mission to Mars:
Concept 2-4-2

 

Jean Marc Salotti

Laboratoire Intˇgration du Matˇriau au Syst¸me

Bordeaux, France

 

ABSTRACT

 

We propose a simplified scenario for a manned mission to Mars. In the last reference mission from NASA, it is shown than the main risks and uncertainties are linked to the mass that has to be sent to LEO (IMLEO) and to the mass of the spacecraft that have to land on Mars. In order to minimize IMLEO, the simplest idea is to reduce the crew to only two astronauts. In order to minimize the mass that has to land on Mars, the key idea is to land 2 spacecraft and to leave the return vehicle in Mars orbit. What remains in orbit is only a small propulsion system, a small Earth reentry capsule and containers with consumables for the return. Such constraints suggest a different approach. Instead of preparing the return vehicle before the manned spacecraft is launched from Earth like in Mars Direct or Mars semi-direct, ISRU systems and astronauts are sent to Mars at the same time and the mission is fully duplicated as it was proposed by Von Braun for security reasons. The name of the scenario is 2-4-2 because there are 2 astronauts in each spacecraft, there are 4 astronauts on Mars who can collaborate and they are 2 once again in each spacecraft for the return. Moreover, in case of emergency, there are always 2 astronauts ready to help the 2 others, even during the transit phases (2 for 2). We show that this scenario optimizes the use of habitable modules and propulsion systems. The habitable modules are indeed sized for 2 and they are occupied during all the mission and the same propulsion system is used for landing and for take-off from Mars. All in all, using only chemical propulsion systems, we show that IMLEO in our scenario is much smaller than the one from NASA reference architecture. Such a scenario could be implemented very soon with minimum R&D.