6 January
1998: On 6 January 1998, NASA launched Lunar Prospector, a satellite designed for a low-polar orbit investigation of the Moon.
After launch, the Lunar Prospector had a 105-hour cruise to the Moon, followed by insertion into a near-circular 100-kilometre altitude polar orbit. In December 1998, the orbit was lowered to 40 kilometres. The nominal mission ended after one year, at which time the orbit was lowered to 30 kilometres.
On 31 July 1999, Lunar Prospector impacted on the Moon near the south pole in a controlled crash to look for evidence of water ice - none was observed.
