CAPE CANAVERAL, Fla. - Two days after Lunar Prospector's suicidal plunge into a crater on the moon, scientists are still unsure if the mission will yield any useful information. The probe crashed into a crater, supposedly filled with ice, in an attempt to kick up a dust cloud that could be analyzed by the Earth-orbiting Hubble Space Telescope and about two dozen ground-based observatories for signs of water.

Lunar Prospector slammed into the moon with the force of a 2-ton truck going more than 1,000 mph at 5:52 a.m. EDT Saturday. The impact was a minute later than original expected because the probe's final engine burn put it into an orbit that was slightly higher than planned. The moment of impact seems to have passed without notice to Earth-bound observers, which included hundreds of amateur astronomers who reported their findings on an interactive Web site.

Flight controllers at NASA's Ames Research Center in Mountain View, Calif., are confident Lunar Prospector completed its kamikaze dive. Radio signals from the craft were eerily absent at the time Lunar Prospector would have emerged from the far side of the moon.

"Once again, Prospector has done everything we have asked of it," said Alan Binder, the principal mission scientist. "The spacecraft performed flawlessly to its very end."

Scientists say the lack of a visible plume from Lunar Prospector's crash does not mean the experiment failed. The key information, if it was captured, will come from observatories equipped with light-splitting spectrographs that can probe for chemical fingerprints of water molecules, or related elements.

Managers say analysis of information collected during the experiment will continue for several days and possibly weeks. The point of the experiment was to try to confirm Lunar Prospector's finding of water on the moon - a discovery that could reshape human exploration and development of the moon.