ACE Weekly 02/06/2008 - 02/12/2008 All ACE spacecraft subsystems are performing nominally. ============================================================================ Orbit/Attitude: Type Attitude Date 02/08/2008 DOY 039 2008 Thrusters 2R 4R+ 4R- Duration 12:35 min Start 20:11:48z Stop 20:24:23z HGAStart -7.16deg HGAStop +7.19deg SunStart 5.92deg SunStop 16.12deg Nutation 0.17deg Firing 64 pulses FuelUsed 0.2080lbs FuelRemain 151.5684lbs FinalSCMass 1385.828lbs The next attitude maneuver is scheduled for Tuesday, 02/19/2008. ============================================================================ OCRs: DOY 043 (02/12/2008) 2032-2034z SEP-111 SEPICA baseline subtraction for event processing was reinstated. This is helpful for weak signals. Baseline subtraction was disabled when internal stimulation was disabled during OCR SEP-110 (2007-332-20:13z). ============================================================================ Activities: None ============================================================================ Anomalies: Update: MOC operations are now using the string 1 ground system. DOY 038 02/07/2008 S-ACE-0274 G08-0014 DSS-66 Unable to Send CMDs DSS-66 was unable to transmit commands received via SLE. The station performed a TCP reboot and commands were successful (DR#M104658). Note, DSS-46 has had successful passes since 12/31/2007. This was the first DSS-66 pass since 11/30/2007. IMPACT: Activities delayed 12 minutes. The next DSS-66 pass (Friday 02/15/2008) will be monitored for CMD problems. DOY 039 02/08/2008 S-ACE-0275 G08-0015 DSS-66 Red Due to Power Failure DSS-66 was unavailable due to a complex-wide power failure (DR#M104665). Antenna maintenance released time with DSS-27 so that the attitude maneuver could be completed. IMPACT: The spacecraft had 18 hours before the 8 degree antenna constraint would have been violated and 2 days before reaching 10 degrees. If the spacecraft did go beyond 10 degrees and high-rate telemetry was no longer available through the Hi-Gain Antenna (HGA), an attitude maneuver could easily be performed at low-rate on the HGA or on the broadbeam antenna if necessary. DOY 039 02/08/2008 S-ACE-0276 G08-0016 ROBOTT/C&C Froze The ACE MOC automation software (ROBOTT) froze during the procedure S_OPS_PLBK_COMPLETE. RTMON restart not performed since less than 15 minutes before End of Track. CDSID#00021192 IMPACT: This is a recurring issue that the ROBOTT developers are aware of. Procedure G_ACEDOWN not performed. This last occurred on 01/17/2008. DOY 043 02/12/2008 S-ACE-0277 G08-0017 DSS-27 Antenna Stop DSS-27 antenna stopped tracking at 2114z. Station reset Antenna Pointing Controller and tracking resumed at 2131z (DR#G108342). IMPACT: 17 minute data gap will be redumped on following pass.