A cropped image of Earth-moon-Mars Lagrange point relationships from the NASA website.
NASA is has some ideas about developing a space base from its parts of the International Space Station when it is dismantled in the future, to act as a staging area for future moon and Mars missions. According to PC Mag author Damon Poeter, apparently it will be positioned at a lagrange point some 61,000km from the moon, and 443,000km from Earth.
According to Wikipedia, lagrange points are:
“the five positions in an orbital configuration where a small object affected only by gravity can theoretically be part of a constant-shape pattern with two larger objects (such as a satellite with respect to the Earth and Moon). The Lagrange points mark positions where the combined gravitational pull of the two large masses provides precisely the centripetal force required to orbit with them”
This is all to go hand-in-hand with NASA’s new SLS (Space Launch System) that is in development and due for first testing in 2014.
(UPDATE)
Mark Whittington from Yahoo! News discusses the challenges of NASA’s emerging ‘beyond moon’ lagrange point plans. Large distances for resupply and positioning outside of the Earth’s magnetic field are obvious hurdles for the space station concept.
Earth’s 5 lagrange points relative to the moon’s influence. Lagrange point L2 is the proposed point of NASA’s spacestation (image source: Wikimedia Commons)
Unless NASA plans to use it as a space re-fueling depot, critiques suggest the space station will not serve a real purpose.
Also a lot of great info and images here @ Space.com and @ here as well
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