ACE Weekly 06/23/2010 - 06/29/2010 All ACE spacecraft subsystems are performing nominally. ======================================================================== Orbit/Attitude: No maneuvers were completed this week. The next attitude maneuver is scheduled for Thursday 07/01/2010. ======================================================================= OCRs: None ======================================================================== Activities: Data Capture: 100% DOY 171-178 2010 ======================================================================== Anomalies: DOY 175 06/24/2010 S-ACE-0516 G10-0034 Incorrect Clock Calibration The procedure, ace_pass.proc, calculates a clock calibration at the end of each pass using the support's telemetry file. The anomalous clock calibration was calculated on a day when the BOT time was on a different DOY than the BOA (BOA was on DOY 174 and BOT was on DOY 175). The clock calibration report was generated and automatically delivered during post-pass activities at 175/0345z. NOAA notified the FOT that they were unable to process telemetry at 175/1214z. As a result, the FOT decided to staff the next ACE support scheduled to start at 175/1520z. The bad clock calibration problem was realized at 175/1600z and a corrected clock calibration report was delivered to NOAA and ASC at 1608z. IMPACT: FOT reloaded End of Track (EOT) time tag loads at 175/1617z. NOAA unable to process ACE RTSW until clock calibration was corrected (~12 hours). MOCR 183 has been implemented to keep track of the telemetry filename created for each pass. MOCR 185 has been implemented to send an email notification if the clock calibration results are bad. Background Information ACE does not have an onboard UTC clock. It has a counter that increments roughly once per second. On the ground the counter is converted to a time. UTC = (slope * SpacecraftCounter) + offset + epoch - leap seconds The slope and offset values are sent to ASC and NOAA in the clock calibration report each day. The epoch is DOY 237 1997 at 15:46:28z. NOTE, WIND anomaly reports will be included when problems with MMOC software/equipment would have impacted ACE operations. Note that the ITOS tm_controller problem occurs randomly, half of the time before ACE passes and half of the time before WIND passes. DOY 174 06/23/2010 S-WIND-0446 ITOS tm_controller Before Beginning Of Track, ITOS had problems connecting telemetry, "timeout reading from tm_controller". ITOS was stopped and restarted and the WIND pass was taken successfully. This problem occurs approximately once every 2 weeks. DR CDSID#00027515 has been submitted for ITOS developers. IMPACT: Manual intervention required.