space.com video: Animation of Lunar Prospector crashing into Moon (201k)

A few weeks ago, a handful of observatories had signed up to watch for signs for the probe's plunge into a supposed ice-filled crater on the moon.

Now, the list is 25 and growing, say experiment organizers with the University of Texas, which will be using three telescopes at the McDonald Observatory to try to scan for water vapor in the dust cloud kicked up by the probe's crash.

Hundreds of amateur astronomers also are coordinating plans to train their telescopes on the moon at 5:51 a.m. EDT on Saturday.

The schedule for the probe's demise was chosen so that the moon would be visible at night from Hawaii and Texas, where the primary telescopes for the experiment are located. It also was based on the availability and positioning of the Hubble Space Telescope, which is orbiting about 300 miles above Earth.

The primary telescopes participating in the observation are equipped with sophisticated light-splitting spectrographs to analyze moonlight for nearly transparent clouds of water and hydroxyl that astronomers hope will be ejected from Lunar Prospector's gravesite.

The point of crashing the probe into the crater is to try to ascertain if there is water on the moon - a resource that could change the pathway of space exploration and development.
While normal amateur telescopes usually are not equipped to scan for chemical fingerprints in light, backyard astronomers may be able to detect a plume of lunar soil, perhaps stretching as has as 20 miles, as the probe slams into the crater's floor. Scientists say that if the plume rises high enough to clear the rim of the crater, the dust cloud might be visible for a short time. It also might glow faintly for several minutes against the black sky, just above the lunar limb.