The internal atmospheric pressure of NASA's Orion crew exploration vehicle could be the same as an airliner. The atmospheres inside NASA's Moon and Mars vehicles are being studied with a view to aiding the needs of extra vehicular activity.
Astronauts may have to conduct EVAs from the crew exploration vehicle during its 4.5-day transit to the Moon docked with the lunar surface access module (LSAM). Atmospheric pressure equivalent to 6,500ft (2,000m) altitude, similar to that in the cabin of the Boeing 787, or up to 8,000ft, which is typical of a current generation airliner, are being considered. The Space Shuttle's crew compartment has a sea-level atmospheric pressure.
The lunar lander atmospheric pressure needed for surface operations may differ from that in Orion. "The LSAM may not necessarily have the same atmosphere as Orion," says NASA Constellation programme medical operations specialist and flight surgeon Richard Scheuring, speaking last week at the 16th IAA Humans in Space symposium in Beijing, China.