Clementine 2 was killed because it was not perceived that it was an important enough project to undertake at this time. We will have to wait until a city gets wiped out before we start thinking of planetary defense in a serious way. During the Gulf War, a meteor entered the atmosphere over the Pacific, I believe, and detonated with the force of a small nuclear bomb. If that had happened over Israel during the 'scud' attacks by Iraq, you can be certain that this natural event would have immediately been regarded as a nuclear strike against Israel, and we would have had a nuclear war on our hands.
The Clementine 1 Mission, on the other hand, was hugely successful and you can look at the NASA Resource Page to get a good summary of what they discovered. The above image shows the lunar north pole where substantial quantities of water ice have been discovered in the permanent shadows of the craters there.
On 5 March 1998 it was announced that data returned by the Lunar Prospector spacecraft indicated that water ice is present at both the north and south lunar poles, in agreement with Clementine results for the south pole reported in November 1996. The ice originally appeared to be mixed in with the lunar regolith (surface rocks, soil, and dust) at low concentrations conservatively estimated at 0.3 to 1 percent. Subsequent data from Lunar Prospector taken over a longer period has indicated the possible presence of discrete, confined, near-pure water ice deposits buried beneath as much as 18 inches (40 centimeters) of dry regolith, with the water signature being stronger at the Moon's north pole than at the south (1). The ice was thought to be spread over 10,000 to 50,000 square km (3,600 to 18,000 square miles) of area near the north pole and 5,000 to 20,000 square km (1,800 to 7,200 square miles) around the south pole, but the latest results show the water may be more concentrated in localized areas (roughly 1850 square km, or 650 square miles, at each pole) rather than being spread out over these large regions. The estimated total volume of ice is 6 trillion kg (6.6 billion tons). Uncertainties in the models mean this estimate could be off considerably.
Copyright 1997 Dr. Sten Odenwald
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