ACE Weekly 11/01/2011 - 11/07/2011 All ACE spacecraft subsystems are performing as expected. ======================================================================== Orbit/Attitude: Type Attitude Date 11/01/2011 DOY 305 2011 Thrusters 2R 4R+ 4R- Duration 15:01 min Start 13:25:08z Stop 13:40:09z HGAStart -7.20deg HGAStop +7.87deg SunStart 12.04deg SunStop 5.43deg SpinStart 5.0262rpm SpinStop 5.0293rpm Nutation 0.04deg Firing 76 pulses FuelUsed 0.2401lbs FuelRemain 126.0500lbs FinalSCMass 1360.310lbs The next attitude maneuver is scheduled for Friday 11/11/2011. ======================================================================= OCRs: None ======================================================================== Activities: Data Capture: 100% DOY 303-310 2011 ACE will be crossing near, but not quite in front of, the sun in the coming week. The sun's radius is ~0.26 degrees. Date DOY SEV Angle Station --------- --- ----------- -------- Sun 11/13 317 0.5 degrees DSS-27 Mon 11/14 318 0.4 degrees DSS-27 Tue 11/15 319 0.5 degrees DSS-27 Previously, ACE has had 4 passes near these angles of which 3 passes had no problems. ======================================================================== Anomalies: DOY 310 11/06/2011 S-ACE-0631 G11-0057 DSS-27 Antenna Stop DSS-27 ground antenna unexpectedly stopped tracking at 1656z, 2 hours after Beginning Of Track. Ground station reset antenna and resumed tracking at 1706z and uplink restored at 1712z. DR#G112102 IMPACT: No data to NOAA SWPC for 10 minutes. Recorded data gap dumped at end of pass. DOY 311 11/07/2011 S-ACE-0632 G11-0058 ITOS crashed The MMOC mission software (ITOS) crashed 5 minutes after Beginning Of Track. ITOS was manually restarted within 15 minutes. ITOS crashes every ~2 weeks, but usually at the end of a pass and the system is configured to restart ITOS when that occurs. This crash occurred during a pass for which the automatic restart is not designed. The CPU usage was high due to ITOS event/postmaster (CDS DR#00027701) and was likely the cause of the crash. IMPACT: No data to NOAA SWPC for 3 minutes during the system restart.