ACE Weekly 11/25/2009 - 12/01/2009 All ACE spacecraft subsystems are performing nominally. ======================================================================== Orbit/Attitude: Type Attitude Date 11/30/2009 DOY 334 2009 Thrusters 2R 4R+ 4R- Duration 15:22 min Start 16:17:15z Stop 16:32:37z HGAStart -7.55deg HGAStop 7.71deg SunStart 12.52deg SunStop 5.95deg SpinStart 5.0348rpm SpinStop 5.0391rpm Nutation 0.14deg Firing 78 pulses FuelUsed 0.2455lbs FuelRemain 139.4208lbs FinalSCMass 1373.681lbs The next attitude maneuver is scheduled for Friday 12/11/2009. ======================================================================= OCRs: None ======================================================================== Activities: Data Capture: 99.99% DOY 326-333 2009 31 second gap due to pass lost on DOY 329 (2009-330 10:17:38-10:18:08) ======================================================================== Anomalies: DOY 328 11/24/2009 S-ACE-0470 S09-0009 Downlink in LRADC not RTSW On DOY 328, the normal tracking pass scheduled with DSS-24 was taken from the MMOC (Multi-Mission Operations Center). The commanding was performed with new converted procedures. An error in the C_ADC_TO_RTSW_TTBIN procedure caused the spacecraft to switch to Low Rate ADC (Attitude Determination and Control) instead of RTSW (Real Time Solar Wind) at the end of the pass (1840z). IMPACT: NOAA Space Weather Prediction Center was unable to process the LRADC for 24 hours (DOY 328 1840z - DOY 329 1854z). The ACE MOC automation software continually crashed at the next scheduled DSN support on DOY 329 0845z (see AR#G09-0059). A manual pass was scheduled for DOY 329 1845z and NOAA could process data at 1854z. There was no impact to recorded science data. DOY 329 11/25/2009 S-ACE-0471 G09-0059 ROBOTT Crash with LRADC The ROBOTT/C&C software continually crashed during the pass on DOY 329. TPOCC was correctly processing the LRADC telemetry, but some error in ROBOTT/C&C was preventing it from starting the pass. ROBOTT/C&C sent out notifications "CC Ops Paused, Forward Link Down" before each crash. The FOT was unaware that the spacecraft was in LRADC and wrote-off the pass as a loss (the pass was off shift, 3:45am EST). IMPACT: If ROBOTT had started pass activities, NOAA would have been able to start processing the data after a 14 hour gap instead of the 24 hour gap that occurred. A 31 second data gap occurred due to the SSR failover on DOY 330 at 10:17:38z. DOY 335 12/01/2009 S-ACE-0472 G09-0060 DSS-24 Transmitter Red The ground station was unable establish an uplink for commanding. The station replaced a Cisco Catalyst 3500 switch and the uplink was available at 1915z. However, with only 30 minutes to End Of Track (1945z), there was insufficient time to start activities. IMAPCT: There will be a 31 second data gap due to SSR failover DOY 336 ~1025z. The SSR playback will be caught up over the next 3 days. Note: There are many situations where starting ACE playback activities with ground commands is very beneficial. AR#G09-0060 is one of the rare cases where preloaded commands would have allowed for data capture during the pass. All data (minus 31 seconds) will nevertheless be captured.