After forty years of venturing no farther than low Earth orbit, NASA may have decided to establish a manned outpost at a greater distance than humanity has ever traveled before. According to documents seen by the Orlando Sentinel, NASA has chosen a proposal to build a space station beyond the Moon that will act as a “gateway spacecraft” to explore the Moon, the asteroids and eventually as a staging post to launch a manned mission to Mars.
The documents refer to a project that NASA Chief Charlie Bolden briefed the White House on earlier this month. They describe a deep space habitat that would be built at Earth-Moon Lagrange 2 (EML-2) – a point in space 38,000 miles (61,000 km) on the far side of the Moon and 277,000 miles (446,000 km) from Earth. The outpost wouldn’t orbit the Moon. Instead, at EML-2 the gravitational and centrifugal forces of the Earth and Moon balance out and an object placed there will remain suspended like one of those desktop novelty floating globes.
The EML-2 station might be built from parts of the International Space Station (ISS) and include a Russian module and Italian components. NASA’s Space Launch System (SLS), scheduled to fly in 2017, would be used to send the components to EML-2 in 2019, as well as the Orion spacecraft, which would ferry cargo and crew to the outpost.
Missions for the EML-2 station would include exploration of the asteroids, robotic trips to the Moon with the first sample returns by 2022, and a manned mission to Mars. The Sentinel quotes the documents as stating that placing a "spacecraft at the Earth-Moon Lagrange point beyond the moon as a test area for human access to deep space is the best near-term option to develop required flight experience and mitigate risk.”
The price of the program isn’t mentioned and this might be a stumbling block for administration support during a time of tight budgets. The White House did not respond to the Orlando Sentinel’s request for comment, and a NASA statement was noncommittal about the outpost.
All this sounds very similar to the 2011 Global Exploration Roadmap drawn up by the International Space Exploration Coordination Group (ISECG), a consortium made up of the ISS partner nations. It outlines possible missions for the next 25 years that could be made possible by extending the service life of the ISS beyond 2020
This report outlined two paths, one called Asteroid Next, which describes the steps needed to explore near-Earth asteroids and Moon Next, which outlines a manned return to the Moon. The EML-2 station appears to be derived from the Asteroid Next path. Whether this is actually the case or not remains to be seen, but the general description from the Sentinel and the Roadmap’s more detailed treatment show no major variations.
If the EML-2 station is approved, it will involve more challenges than the merely monetary. EML-2 lies far outside the Earth’s Van Allen belts and would therefore be vulnerable to high levels of radiation, which would require robust shielding and detection equipment. The Orion spacecraft would also have to be built to withstand reentry speed not encountered since the return of Apollo 17 in 1972.
Because of the distance and travel times to and from Earth measuring in days, systems would need to be heavily automated and built to an unprecedented degree of reliability. Furthermore, new techniques for the long-term storage and management of cryogenic fluids would need to be developed as well as acquiring operational knowledge that is beyond anything needed in manned space exploration to date.
Until officially verified, the EML-2 station still remains only one possible future for the American space program, but if it does come about, the final frontier will have expanded enormously.
Sources: Orlando Sentinel,