|
|
Operations CXO Status Report
Friday 9 May 2003, 8.00am EDT
The observing schedule was interrupted at 4:08pm on 8 May due to a
high radiation event that activated the science instrument safing
sequence (SCS 107). The high radiation was associated with an active
coronal stream as Chandra approached the radiation belts. The loads
have been replanned to start at 9:39am on May 9. The observation of
Sco X-1 was impacted by the event (total 14Ks science time). Future
loads will include an increased radiation belt pad time to try and
avoid a similar trip.
A real-time procedure was completed on May 6 to perform a manual
unload of momentum using thrusters A-1 (100%), A-2 and A-4. 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 indicates that the thermal environment
is related to the prior anomalous performance.
Real time procedures were completed on May 6 to perform a truncated
ACA dark current calibration in support of a DSN Network
Simplification Project test using DSS-59, and on May 8 to lower the
ACA CCD temperature from -10 to -11 deg C to mitigate the increasing
number of warm pixels. The ACA CCD will be lowered in a series of 1
deg steps to -15 deg C to allow for performance assessment.
The IRU-1 gyro-1 current remained at ~150mA (its yellow limit) with
continued noisy behavior.
The observing schedule for next week is shown below and includes an
observation of Mkn 279 coordinated with HST and FUSE.
|
------------------------------------------
RCW103 ACIS-I May 4
SDSS J222845-075755 ACIS-S
DOAR 21 ACIS-S/HETG May 5
Radiation Belts May 6
PDS 456 ACIS-S/HETG
Sco X-1 ACIS-S/HETG May 8
Radiation Belts
MXB 1659-298 ACIS-S May 9
G11.2-0.3 ACIS-S
MRK 279 HRC-S/LETG May 10
HD110073 ACIS-I
NGC 1800 ACIS-S
------------------------------------------
All spacecraft subsystems, with the exception of the MUPS thruster A-1
under investigation, continued to operate nominally.
Return to 2003 Status Reports |
