ACE Weekly 11/13/2013 - 11/19/2013 All ACE spacecraft subsystems are performing as expected. ======================================================================== Orbit/Attitude: Type Attitude Date 11/18/2013 DOY 322 2013 Thrusters 2R 4R+ 4R- Duration 7:24 min Start 17:27:38z Stop 17:35:02z HGAStart -8.22 deg HGAStop +9.00 deg SunStart 11.25 deg SunStop 16.49 deg SpinStart 4.9710 rpm SpinStop 4.9725 rpm Nutation 0.09 deg Firing 37 pulses FuelUsed 0.1211 lbm FuelRemain 110.4136 lbm FinalSCMass 1344.674 lbm The next attitude maneuver is scheduled for Tuesday 11/26/2013. ======================================================================== OCRs: None ======================================================================== Activities: Data Capture: 100% DOY 314-321 2013 On 11/15/2013, DSN's new Data Capture and Delivery software (DCD v4.1) was tested with simulated data from DSN's Test Facility (DTF-21). No problems were found during the 1.5 hour data flow. ======================================================================== Anomalies: Update for S13-0001 Tank Temperature & Spin Rate Anomaly On 9/19/2013 (DOY 262), the B1 Fuel Tank temperature had jumped from 18.4°C to 20.3°C and finally settled between 19.1 and 19.7°C (temperature resolution 0.63°C). This also corresponded to a 0.01% increase in the spacecraft spin. The current theory is that a warmer part of the spacecraft came in contact with the B1 Fuel Tank, with the lower final temperature indicating a loose thermal contact. During the maneuver on 11/05/2013 (DOY 309), the B1 Fuel Tank temperature increased again to 20.9°C. The current theory is that the warmer part of the spacecraft has made a better thermal contact with the B1 Fuel Tank resulting in the increased temperature. These spikes, along with the annual temperature fluctuations, can be seen in the plot provided by the ACE Science Center. http://www.srl.caltech.edu/ACE/ASC/DATA/housekeeping/temperatures/gifs/TankB1.jpg The other tank temperatures are available at http://www.srl.caltech.edu/ACE/ASC/DATA/housekeeping/temperatures/gifs/TankA1.jpg http://www.srl.caltech.edu/ACE/ASC/DATA/housekeeping/temperatures/gifs/TankA2.jpg http://www.srl.caltech.edu/ACE/ASC/DATA/housekeeping/temperatures/gifs/TankB2.jpg http://www.srl.caltech.edu/ACE/ASC/DATA/housekeeping/temperatures/gifs/