ACE Weekly 12/03/2008 - 12/09/2008 All ACE spacecraft subsystems are performing nominally. ============================================================================ Orbit/Attitude: Type Attitude Date 12/03/2008 DOY 338 2008 Thrusters 2R 4R+ 4R- Duration 12:17 min Start 15:49:31z Stop 16:01:48z HGAStart -5.73deg HGAStop 7.60deg SunStart 13.22deg SunStop 5.26deg Nutation 0.06deg Firing 62 pulses FuelUsed 0.2044lbs FuelRemain 146.3024lbs FinalSCMass 1380.562lbs Note: The nutation calculation has been corrected. Previously reported values had an extra factor of two. The next attitude maneuver and SK-49 are scheduled for Wednesday 12/10/2008. =========================================================================== OCRs: None ============================================================================ Activities: Data Capture: 100% DOY 335-342 2008 There is a higher than normal risk of data loss from October 2008 through February 2009. If there are problems with the passes, it may not be possible to acquire additional DSN time. This higher-risk period has been occurring every winter for the past couple of years. For more information refer to 10/14/2008 weekly. ============================================================================ Anomalies: DOY 336 12/01/2008 S-ACE-0390 G08-0123 ROBOTT/C&C Terminated Procedure The MOC automation software, ROBOTT, prematurely terminated the SSR redump procedure (s_ops_plbk_complete.prc). ROBOTT did not see that the previous procedure had completed and terminated all procedures. This is a known issue (CDSID#21122) which last occurred on 10/21/2008 (AR#G08-0101). IMPACT: Minimal. No redumps were required. DOY 336 12/05/2008 S-ACE-0391 G08-0124 Large Range Drifts in Track Data DSN Uplink software (UPL V8.1) has the wrong value in the secondary header of the Uplink Sequential Range Phase data (USRP). The error was first noticed 11/22/2008 and affects all missions using Range Track Data. DSN is looking at workarounds to this problem. A new software delivery is expected soon for the Goldstone site and for Madrid & Canberra in the following week. DR#N105028. IMPACT: Invalid range data could adversely affect FDF Orbit Determination. ACE Orbit Determination was performed on 12/09/2008 in preparation of SK-49.