Lunar Prospector Status Report #45

August 21, 1998 - 1:00 p.m. EST (10:00 a.m. PST)

The Lunar Prospector spacecraft continues to perform very well.

Thrusters were fired last week to recircularize the spacecraft's orbit. Analysis by the navigation team at GSFC indicates that the maneuver went very well. The timeline was as follows (all activities were on 8.17, Day of Year 229; times are GMT):

- 1604 thruster heaters on

- 1634 fire A3/A4 thrusters for 42.3 seconds to increase the velocity by 6.42 m/s

- 1715 thuster heaters on

- 1741 fire A3/A4 thrusters for 45.0 seconds to decrease the velocity by 6.83 m/s

- 1756 thruster heaters on

- 1801 fire T1 thruster for 0.75 seconds to return spin rate to 12 rpm

The maneuver was estimated to use 1.2 kg of propellant, leaving 27.75 kg remaining (20%).

Current spacecraft state (0000 GMT 8/21/98):

Orbit: 2692
Downlink: 3600 bps
Spin Rate: 12.00 rpm

Spin Axis Attitude (ecliptic):
Latitude: 88.8 deg
Longitude: 152 deg

Trajectory:
Periapsis Alt: 90.6 km
Apoapsis Alt: 105.7 km

Inclination: 90.6 deg
Period: 118 min
Occultations: 34 minutes
Eclipses: 41 minutes