NASA is planning to make the first permanent human habitat in deep space.
Budget limitations, however, pose challenges to such an endeavor, so NASA has decided to take an alternate route, incorporating the project into something for which they already have funding.
Specifically, NASA is considering using the upper-stage hydrogen propellant tank of its massive Space Launch System rocket. According to researchers, the tank would make for a comparatively cheap option. NASA is calling the planned spacecraft "Skylab II" after the 1970s Skylab space station that was an enhanced third stage of a Saturn V moon rocket.
"This idea is not challenging technology," Brand Griffin, an engineer with Gray Research Inc. who also does work for the Advanced Concepts Office at the NASA Marshall Space Flight Center, said. "It's just trying to say, 'Is this the time to be able to look at existing assets, planned assets and incorporate those into what we have as a destination of getting humans beyond LEO [low-Earth orbit]?'"
NASA plans to use its Space Launch System (SLS) to send astronauts back to the Moon, near-Earth asteroids and, potentially, even Mars. The rocket is 384 feet long and can carry 130 tons of cargo. It is scheduled for a test launch in 2017.
Compared with modules in the International Space Station, the tank of the SLS is much larger, having about the volume of a two-story house. Accordingly, it could carry a crew of four comfortably and hold enough food and supplies for several years. It would also be launched by the SLS in one piece, unlike the ISS, which would require multiple launches.
"We will have the facilities in place, the tooling, the personnel, all the supply chain and everything else," Griffin said.
The idea is similar to the original Skylab station, built by NASA during a time of budget turmoil following the Apollo boom.
"In many ways, this could follow that same pattern," Griffin said. "It could be a project embedded under SLS and be able to, ideally, not incur some of the costs of program startup."
NASA hopes to place Skylab II on an area of the moon called the Earth-moon Lagrange point 2. A manned outpost there would be a launching point for operations on the moon and also help foster exploration of further locations, including asteroids and Mars.
