NASA's Lunar Prospector hit the south pole of the moon as planned on 31 July, but no vapour plume was detected after the impact. Scientists hope that an as-yet undetected faint plume may contain traces of either water or the hydroxyl radical formed when sunlight splits a hydrogen atom away from a water molecule.

The detection of water would support theories that the moon's polar regions could contain water ice beneath the surface.

The Lunar Prospector was launched on an Athena booster from Cape Canaveral, Florida, in January 1998.

Meanwhile, US company TransOrbital plans to launch a privately funded lunar orbiter, TrailBlazer, in December next year to take live, high-resolution telephoto images of the surface from an altitude of 100km.

The images, which will show the tracks left by the Apollo lunar rovers and pictures of the earth rising, will be available to up to 75,000 paying clients. The $1 million craft would operate for a maximum of 90 days before hitting the moon.

Source: Flight International