— Like the International Space Station now, the future Moon base will be permanently occupied by rotating crews (Illustration: NASA)
Robots will be a key part of the new exploration of the Moon, but NASA will seek international and commercial partners to provide the technology (Image: NASA)
NASA plans to permanently occupy an outpost at one of the Moon's poles, officials announced on Monday.
The first four astronauts will land for a short visit in 2020, but it will take until at least 2024 to prepare for "a fully functional presence with rotating crews", said Scott Horowitz, associate administrator for the exploration systems mission directorate.
It has taken NASA nearly three years to get to this point in their planning, following President George W Bush's announcement of his "vision" for exploring the Moon and Mars).
In April 2006, representatives of NASA and 13 other space agencies met to plan themes and objectives for an exploration strategy essentially why to return to the Moon and what to do there. (NASA videos relating to the six themes decided upon are available.)
The planned base on the Moon is now a key part of the strategy. But NASA will not be going it alone. "It is critical we have international participation and commercial participation," says NASA deputy administrator Shana Dale, although no agreements are yet in place.
"The US will build the transportation infrastructure," said Dale. NASA will also provide initial capabilities for communications, navigation, and operation around the base. But the US is seeking help from other countries and private corporations in other areas, including the lunar habitation modules, power, logistics and robotics.
The first full-scale test of the new US Ares 1 rocket is set for 2009 using a dummy second stage. An active second stage will be tested until 2012, and the launcher will not fly with a human crew until 2014, four years after NASA plans to ground the shuttle fleet.
Money for the ambitious plans will come from phasing out the shuttle. NASA does not expect a boost above its current 0.6% of the US budget, Horowitz said.
The first lunar explorers will be robots. Set for launch in October 2008, the Lunar Robotic Orbiter will target the poles to help select where to place the lunar outpost. Some spots near the poles appear to be sunlit 70% to 80% of the time, promising power for solar cells and more moderate temperatures than in areas cycling between the extremes of night and day.
Mountains keep the floors of some polar craters in perpetual shade, so volatile compounds such as water should have accumulated for billions of years. However, hopes for finding large quantities of ice at the south pole have dimmed recently (see Hopes for lunar ice melt away).
But the Moon's polar regions are hard to study from Earth, so Horowitz says an orbiter will provide vital new information. A robotic lander would then visit the selected site after 2010.
The lander that delivers astronauts to the lunar surface will be crucial, Horowitz noted. In order to deliver the materials to the surface for constructing the base, the mass landed will need to be maximised and the mass of the ascent module minimised.
Another "basic high-level requirement" for the lander is to be able to go everywhere on the Moon, says Horowitz.
How fast the base expands and how many people work there will depend on how many other organisations become involved, but he says "it's obviously too early" to say what visitors would pay for a night's stay at the outpost.