Revised scenario for human missions to Mars

We present a revised version of our scenario for human missions to Mars. The idea is to take into consideration the difficulties and constraints for entry, descent and landing by splitting the heavy vehicle into two smaller ones. The standard capsule shape is thus possible for aerocapture and landing on Mars. It is suggested to use the largest possible diameter such that the ballistic coefficient is minimized and the lift to drag ratio is kept small. The maneuvers for the descent and landing are then simplified and the risks are minimized. The scenario has been modified to cope with the new constraints. Different options have been taken into account. It is possible to land a small Mars ascent vehicle or to reuse the habitat lander for Mars ascent. All options perform as well as the others for the criterion of the initial mass in low Earth orbit. However, reusing the habitat lander allows a significant reduction of the size of the Earth return vehicle, which otherwise requires a huge launching capability.

► The landing with very light vehicles reduces the risks.
► The maximum mass for the vehicle can be computed. It is equal to 32 tons.
► A small capsule can be waiting in Mars orbit instead of a full habitat.
► The total mass of each TMI vehicle is between 79 and 100 tons.
► Thanks to the numerous backup options, the proposed scenario is very robust.