Flight has obtained details of the international Mars Sample Return (MSR) mission architecture that is to be presented at a European Space Agency, French space agency CNES hosted conference in Paris on 9-10 July.

While the architecture envisages a number of launch dates from 2018 for the MSR mission, the overall concept is an orbiter to be launched up to two years before the lander, which has a rover and a Mars Ascent Vehicle (MAV) that will return samples to Earth.

The mass estimate for the combined lander, MAV, rover is 4,800kg (10,500lb). The United Launch Alliance Atlas V in a 5.4m fairing, five solid rocket boosters and a single-engine Centaur stage configuration is the current designated launcher. It can deliver 4,900kg to the transfer orbit required in 2020. Despite a number of launch options being in the 2020s NASA's proposed Ares V cargo launch vehicle is not a part of the architecture.

The architecture was drawn up by the International Mars Architecture for the Return of Samples group, known as iMARS. According to iMars' draft development timeline a 2020 lander launch requires MAV phase 0 work to start next year as would its orbiter's with "technology maturation" for both envisaged to start now.

A 23 June presentation to the Texas-based Lunar and Planetary Institute's planetary science subcommittee by NASA MSR programme executive member Lisa May states that: "[The] time to collect samples is a key trade. MAV and rover lifetimes are factors."

Despite the forthcoming conference ESA was not available for comment. NASA and ESA held bilateral meetings on MSR in October 2007 and January and May of this year. The iMARS met in September and November 2007 and March this year.

The lander's mass will in-part be dictated by a decision on how far the rover would roam to collect samples. NASA's own Mars Architecture Tiger Team, which met in this year's second quarter, proposed a "caching" rover sent to collect samples before the MAV's lander arrives.

The next eighteen months could also see the selection of the site for the Martian samples receiving facility.

Source: Flight International