Mapping the Moon

According to

Vision for Space Exploration, astronauts will return to the Moon as early as 2015. On the Moon, astronauts will learn how to live on an alien world before attempting longer voyages to other planets such as Mars.

However, current maps of the Moon are not very precise. In some areas, near Apollo landing sites, the locations of craters and ridges are well known as they were extensively photographed by lunar orbiters and Apollo astronauts. But much of the lunar surface is known only approximately.

"If you ask 'where is a crater on the far side of the Moon?' chances are there's probably many kilometres of uncertainty in its true positioning," says David Smith, a scientist at NASA's Goddard Space Flight Center. Even on the near side of the Moon, Smith adds, errors in the true global position of features may be as large as a kilometre.

To improve this situation, NASA plans to send a high-precision laser altimeter to orbit the Moon and create a 3D map of its surface.