An artist’s rendering of Lunar Prospector in orbit around the Moon.
Image: Lunar and Planetary Institute.

In 1998 on this date, the unmanned probe Lunar Prospector was launched from Cape Canaveral. This one-year-long program was designed for a low-polar-orbit investigation of the Moon, including (among other things): mapping of surface composition and possible polar ice deposits, and measurement of magnetic and gravity fields. Check out NASA’s Mission Archive page here.