ACE Weekly 05/20/2009 - 05/27/2009 All ACE spacecraft subsystems are performing nominally. ======================================================================== Orbit/Attitude: Type Attitude Date 05/26/2009 DOY 146 2009 Thrusters 2R 4R+ 4R- Duration 14:02 min Start 14:46:42z Stop 15:00:44z HGAStart -7.15deg HGAStop +7.45deg SunStart 14.34deg SunStop 5.06deg SpinStart 5.0154rpm SpinStop 5.0203rpm Nutation 0.20deg Firing 71 pulses FuelUsed 0.2307lbs FuelRemain 142.9752lbs FinalSCMass 1377.235lbs The next attitude maneuver is scheduled for Friday 06/05/2009. ======================================================================= OCRs: None ======================================================================== Activities: Data Capture: 100% DOY 137-144 2009 ======================================================================== Anomalies: DOY 141 05/21/2009 S-ACE-0442 G09-0037 DSS-54 Telemetry Processor The ground station's Telemetry Processor (TLP) was unable to process telemetry after establishing the uplink. The TLP started working at 1417z. DR#M105358 IMPACT: Activities delayed 16 minutes. DOY 146 05/26/2009 S-ACE-0441 G09-0036 DSS-27 Receiver Problems The ground station was unable to lock onto telemetry after establishing the uplink. The station switched to a second receiver. DR#G109466 IMPACT: Activities delayed 10 minutes. Background Information. ACE playback is initiated via ground command (as opposed to spacecraft load). This gives ACE considerable flexibility in moving automated passes. However, this requires that the DSN station operator configure their system for low-rate data (498bps), deliver telemetry to the MOC, wait for the spacecraft to be commanded and then reconfigure their system for high-rate data.