posted 11-15-2009 03:00 PM               

The Lunar Prospector mission was the third selected by NASA for full development and construction as part of the Discovery program.

At a cost of $63 million, the 19 month mission was designed for a low polar orbit investigation of the moon including mapping of the surface composition and possible polar ice deposits, measurements of magnetic and gravity fields and study of lunar outgassing events.

Lunar prospector was launched at 9:28:44 PM EST on January 6, 1998 aboard the maiden flight of the Lockheed-Martin Athena 2 commercial launch vehicle.

The mission ended on July 31, 1999 at 5:52:02 AM EDT when Lunar Prospector was deliberately targeted to impact the moon in a permanently shadowed crater near the lunar south pole. It was hoped that the impact would liberate water vapor from the suspected ice deposits in the crater and that the plume would be detectable from earth, however no such plume was detected.

Two very appropriate stamps was used on this cover. The first stamp used commemorated the Apollo 8 flight to the moon and was issued on May 5, 1969. The other stamp was issued as part of a 10 stamp Space Exploration booklet pane which was issued on October 1, 1991. The other nine stamps depicted the planets and this stamp depicted the moon.