Lunar Prospector Status Report #83

May 21, 1999 - 1:00 p.m. EST (10:00 a.m. PST)

The Lunar Prospector spacecraft continues to collect good science data in the extended mission orbit. All five science instruments are on: the Gamma Ray Spectrometer (GRS), the Neutron Spectrometer (NS), the Magnetometer (MAG), the Electron Reflectometer (ER), and the Alpha Particle Spectrometer (APS). Data continues to be collected for the Doppler Gravity Experiment (DGE) as well.

The transmitter was turned off for short intervals five times this week during eclipse periods when the propellant tank heater was on. The battery voltage dropped to the yellow low limit for 5 heater events and to the red low limit for one event (out of 18 events).
All commands (24 total) executed normally this w

Current spacecraft state (0000 GMT 5/21/99, DOY 141):

Orbit: 6135
Downlink: 3600 bps
Spin Rate: 12.04 rpm

Spin Axis Attitude (ecliptic):
Latitude: -88.6 deg
Longitude: 041 deg

Trajectory:
Periapsis Alt: 16.6 km
Apoapsis Alt: 43.4 km
Period: 111 min

Occultations: 44 minutes
Eclipses: 46 minutes
Propellant Remaining: 11.81 kg
The next orbit maintenance burn is scheduled for June 2, GMT (afternoon of June 1, PST).