Exploration Systems Architecture Study
The Exploration Systems Architecture Study (ESAS) is the official title of a large-scale, system level study released by the National Aeronautics and Space Administration (NASA) in November 2005 of his goal of returning astronauts to the Moon and eventually Mars—known as the Vision for Space Exploration (and unofficially as "Moon, Mars and Beyond" in some aerospace circles, though the specifics of a crewed "beyond" program remain vague).
NASA Administrator Michael Griffin ordered a number of changes in the originally planned Crew Exploration Vehicle (now Orion MPCV) acquisition strategy designed by his predecessor Sean O'Keefe.
Proposals submitted in May 2005 were to be part of the Phase 1 portion of CEV design, which was to be followed by an orbital or suborbital fly-off of technology demonstrator spacecraft called FAST in 2008.
However, with the change of NASA Administrators, Mike Griffin did away with this schedule, viewing it as unacceptably slow, and moved directly to Phase 2 in early 2006.
The performance of the Cargo Shuttle Derived Launch Vehicle (SDLV) would be 125 to 130 metric tons to Low Earth Orbit (LEO).
The in-line option originally featured five throw-away versions of the SSMEs on the core stage, but was changed later to five RS-68 rocket engines (currently in use on the Delta IV Heavy rocket), with higher thrust and lower costs, which required a slight increase in the overall diameter of the core.
[citation needed] The ESAS recommended strategies for flying the crewed CEV by 2014, and endorsed a Lunar Orbit Rendezvous approach to the Moon.
The CEV would be an Apollo-like capsule, with a Viking-type heat shield, not a lifting body or winged vehicle like the Shuttle was.
Landing on the west coast would allow the majority of the reentry path to be flown over the Pacific Ocean rather than populated areas.
The Lunar Surface Access Module, which would later be known as Altair, and heavy-lift booster (Ares V) would be developed in parallel and would both be ready for flight by 2018.
This would allow a derivative of the same lander to be used on later Mars missions, where methane propellant can be manufactured from the Martian soil in a process known as In-Situ Resource Utilization (ISRU).
Artemis will use separately launched landers under the CLPS Program to deliver support equipment for lunar outposts.
The Artemis Program hopes to set up a small international lunar outpost by 2028[citation needed] The use of scalable CEVs and a lander with methane-fueled engines meant that meaningful hardware testing for Mars missions could be done on the Moon.
This resulted in strong objections from the international partners that the US was not meeting its commitments, and concerns in Congress that the investment in ISS would be wasted.
NASA originally sought this combination because it could be "mined" in situ from lunar or martian soil – something that could be potentially useful on missions to these celestial bodies.
In July, 2006, NASA responded to these criticisms by changing the plan to traditional rocket fuels (liquid hydrogen and oxygen for the LSAM and hypergolics for the CEV).
Finally, the decision in 2011 to add an uncrewed test of the Orion on a Delta IV clearly contradicts the ESAS conclusion that this was infeasible.
It covered human spaceflight options after the time NASA had planned to retire the Space Shuttle.
The Committee judged the 9-year old Constellation program to be so behind schedule, underfunded and over budget that meeting any of its goals would not be possible.
These might include international cooperation, developing new industries, energy independence, reducing climate change, national prestige, etc.
Therefore, the ideal destination should contain resources such as water to sustain life (also providing oxygen for breathing, and hydrogen to combine with oxygen for rocket fuel), and precious and industrial metals and other resources that may be of value for space construction and perhaps in some cases worth returning to Earth (e.g., see asteroid mining).
