Operations CXO Status Report

Friday 6 June 2003 12.30pm EDT

During the last week the observing schedule was restarted at 9.00am on May 31 following the interruption due to high solar activity (total 94.8 Ks science time impact). On June 2 the loads were replanned to include an observation of the gamma-ray burster GRB030528 that was accepted as a Target Of Opportunity (TOO). Observations of SN 2000BG, A4038, SDSS J000654.11-001533.4 and 4C 74.26 were impacted by the solar event and TOO and will be rescheduled. The IRU-1 gyro-1 current remained quiet and near 140 mA during the last week. A real-time procedure was completed on Jun 6 to turn on the B-side Inertial Reference Unit (IRU-2). IRU-2 will be operated in parallel with IRU-1 in order to allow calibration of the gyros concurrent with on-going operations. A real-time procedure was completed on Jun 4 to perform a manual unload of momentum. The unload was performed at an attitude that ensured a cooler starting temperature than prior anomalous unloads. Thruster performance was nominal during the unload and provides further evidence that the thermal environment is related to the prior anomalous performance. The observing schedule for next week is shown below and includes and observation of the TOO GRB030528.

------------------------------------------

2MASS012031+2003        ACIS-S       Jun 8
1E0953.8+6918           ACIS-S
GRB030528 (TOO)         ACIS-S       Jun 9
Radiation Belts
1E 1207.4-5209          ACIS-S/LETG  Jun 10
Radiation Belts                      Jun 12
Cetus Field             ACIS-I
Radiation Belts                      Jun 14
Cetus Field             ACIS-I       Jun 15
BR 0418-5723            ACIS-S
1E 1207.4-5209          ACIS-S

------------------------------------------

All spacecraft subsystems, with the exception of the MUPS thruster A-1 under investigation, continued to operate nominally.

Return to Status Reports