NEAR Shoemaker Weekly Report 30 June 2000

MISSION OPERATIONS:
 
During this past week, NEAR Shoemaker remained in Operational Mode with Flight Computer #1 and Attitude Interface Unit #2 in control of spacecraft attitude.  Except for the Near-Infrared Spectrometer (NIS), the spacecraft instrument suite remained "ON" and operational this week.
 
NEAR Shoemaker is presently in a nominal 50 km circular orbit around Eros. The spacecraft entered this orbit April 30, 2000 at 16:15 UTC when Orbit Correction Maneuver 6 (OCM 6) was executed.  According to the current long term trajectory plan, NEAR Shoemaker will remain in this orbit conducting Science observations until July 7, 2000 at 18:00 UTC when Orbit Correction Maneuver 7 (OCM 7) will initiate the 50 km x 35 km transfer orbit.
 
Since the next planned OCM is not scheduled until July 7, weekly Momentum Correction Maneuvers (MCM) are required to manage spacecraft system momentum.  Beginning May 10, these maneuvers are scheduled every Wednesday until June 28.  The eighth. and last, MCM of  this period, MCM 10,  was successfully executed this past Wednesday, June 28, at 16:00 UTC.  The achieved momentum was well within operational tolerances, and the imparted delta V was minor.
 
Four OCM’s are scheduled for July.  These maneuvers will successively place NEAR Shoemaker into a 50 km x 35 km transfer orbit, circularize the orbit at 35 km, reinitialize a 35 km x 50 km transfer orbit, and finally reestablish a 50 km circular orbit.  Dates of these maneuvers are defined below.  During the 35 km orbit, after recovering opnav data associated with OCM 8, four days will be spent sun pointing to refine the gravitational field model, and the remaining duration will be allocated to XGRS for prime science data collection.
 
Except for the NIS, science activities conducted this week included Eros observations by the full instrument suite: MSI, MAG, XGRS and NLR.  Please consult science timelines for more details.
 
Upcoming Spacecraft Activities:
 
In addition to regular Eros Science and Optical Navigation, the following are operationally significant activities planned for the NEAR Shoemaker mission operation:
 
July 7  Eros Orbit Correction Maneuver 7  (50 km  x  35 km transfer orbit)
July 14  Eros Orbit Correction Maneuver 8  (35 km orbit
circularization)
July 24 Eros Orbit Correction Maneuver 9  (35 km  x  50 km transfer orbit)
July 31  Eros Orbit Correction Maneuver 10  (50 km orbit
circularization)