Austere Human Missions to Mars

Austere Human Missions to Mars is a concept for a human mission to Mars by the United States space agency, NASA. Released in 2009, it proposed a modified and even less costly version of Design Reference Architecture (DRA) 5.0, itself a combination of nearly 20 years of Mars planning design work. The mission profile was for a conjunction class with a long surface stay, pre-deployed cargo, aerocapture and propulsive capture, and some in-situ resource production. As of 2015, the concept has not yet been adapted to the Space Launch System that replaced NASA's Constellation program in 2011.

Technologically and financially the concept remains conservative, with both peak yearly and total funding to be less than the ISS up to the first mission. The plan would use standardized systems to launch a crew of 4 every four years, but accomplish the same major goals as DRA 5.0, which included a crew of six.

Scaled down from DRA 5.0 and its requirements, it claims to be still acceptable from a science and exploration standpoint.

Simplifications and cost cutting are obtained mainly by avoiding high risk or high cost technology development and maximizing development and production commonality:

The mission comprises the following basic equipment:

A standardized liquid oxygen/liquid hydrogen (LOX/LH2) propulsive stage, like Ares V or its follower SLS Block II, would send the Descent/Ascent Vehicle (DAV), Mars Surface Habitat and Cargo elements to Mars orbit unmanned. The DAV would aerocapture into Mars orbit, preparing it for rendezvous with the manned Transit Habitat to arrive later. The Surface Habitat and Cargo would likely do direct entry. One advantage of the combined Descent/Ascent Vehicle as the spacecraft used for the manned landing, is that it could perform an abort to orbit. A number of technologies for the descent stages were looked at, especially supersonic retro-propulsion for Mars atmospheric entry, but were otherwise very traditional with a large heat shield and retro rockets for final landing.

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