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NASA's LCROSS mission to the moon last week will have entertained remote sensors. It was an exhibition of high speed sensing as much as anything else.

Typically, space sensors last for years – and scientists and engineers spend months calibrating and testing before the instruments go into service. But in this case, the instruments only had a few seconds to capture the data.

The mission profile was certainly exciting. NASA scientists are searching for signs of water ice on the moon. Some of NASA's own early missions, and the Indian Chandrayaan-1, India's 2008 mission to the Moon, provided hints that water may exist.

NASA's method: fly a spacecraft into the lunar surface, and then analyse the plume from the explosion for signs of water.

The impactor was the Centaur upper stage of the Atlas V launch vehicle. It was guided by a small Sheppard satellite – the Lunar Crater Observing and Sensing Satellite. The aim of LCROSS was to guide the Centaur to a precise point on the lunar surface in the crater Cabeus.

Cabeus was chosen because it is close to the south Lunar pole. The sun never shines into it. If there is any ice at all on the moon, it will be in places such as this.

LCROSS and the Centaur separated just before impact. The Centaur arrived at the lunar surface just four minutes before LCROSS.

LCROSS carried two near-infrared spectrometers, a visible light spectrometer, two mid-infrared cameras, two near-infrared cameras, a visible camera and a visible radiometer. The LCROSS instruments were selected to provide mission scientists with multiple complimentary views of the debris plume created by the Centaur impact.

In those last four minutes, all nine instruments on LCROSS were pointed at the impact site, and transmitted the results back to Earth.

A faint, but distinct, debris plume was visible in the ultraviolet, visible and near infra-red, all of which were imaged by LCROSS.

Anthony Colaprete, the principal investigator said:'There is a clear indication of a plume of vapour and fine debris.

'The ejecta brightness appears to be at the low end of our predictions; this may be a clue to the properties of the material the Centaur impacted'', he said.

But LCROSS may not have the last word. Some 20 telescopes around the world, including the Keck Observatory – currently the largest in the world – also watched the impact. So did the Hubble Space Telescope, GeoEye-1 and Ikonos.

We will have to wait until the data analysis is done find out who saw what.

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