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Table of Contents
Introduction
Mission Profile
LP: Scientific Goals
Scientific Results
Glossary
Download
Full Report
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Mission Profile
At 9:28 p.m. (EST) on January 6, 1998, Lunar Prospector (LP) blasted off to the
Moon aboard a Lockheed Martin solid-fuel, three-stage rocket called Athena II. It
was successfully on its way to the Moon for a one-year, polar orbit, primary mission
dedicated to globally mapping lunar resources, gravity, and magnetic fields, and
even outgassing events. About 13 minutes after launch, the Athena II placed the Lunar
Prospector payload into a "parking orbit" 115 miles above the Earth. Following
a 42-minute coast in the parking orbit, Prospectorís Trans Lunar Injection (TLI)
stage successfully completed a 64-second burn, releasing the spacecraft from Earth
orbit and setting it on course to the Moon, a 105-hour coast. The official mission
timeline began when the spacecraft switched on 56 minutes, 30 seconds after liftoff.
Shortly after turning the vehicle on, mission controllers deployed the spacecraftís
three extendible masts, or booms. Finally, the spacecraftís five instruments -- the
gamma-ray spectrometer, alpha particle spectrometer, neutron spectrometer, magnetometer
and electron reflectometer -- were turned on. On Sunday, January 11, at 7:20 a.m.
(EST), Lunar Prospector was successfully captured into lunar orbit, and a few days
later began its mission to globally map the Moon.
Lunar Prospector is a small,* spin-stabilized spacecraft in a polar orbit with
a period of 118 minutes at a nominal altitude of 100 km (63 miles). Since the Moon
rotates a full turn beneath the spacecraft every lunar cycle (~27.3 days) as it zips
around the Moon every 2 hours, Prospector visits a polar region every hour and completely
covers the lunar surface twice a month. Prospector's one-year-long primary mission
with an optional extended mission of a further 6 months at an even lower altitude
enables large amounts of data to collect over time. For some science instruments,
a significant amount of time is required to obtain high quality usable data. Thus,
Prospector's polar orbit and long-mission time render it ideal from the standpoint
of globally mapping the Moon.
*(1.3m in diameter X 1.4m tall bus with three 2.5 meter science masts carrying
its five science instruments and isolating them from the spacecraft's electronics)
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