ACE Weekly 04/09/2015 - 04/14/2015 ACE spacecraft subsystems are performing as expected. ======================================================================== Orbit/Attitude: Type Attitude Date 04/14/2015 DOY 104 2015 Thrusters 2R 4R+ 4R- Duration 14:25 minutes Start 20:06:47z Stop 20:21:12z ra,decStart 30.25,0.89 ra,decStop 38.55,11.55 ra,decExpect 38.96,11.79 Deviation 0.47deg (-3%) HGAStart -8.17 deg HGAStop +8.51 deg SunStart 11.56 deg SunStop 15.94 deg SpinStart 5.0109 rpm SpinStop 5.0152 rpm Nutation 0.16 deg Firing 73 pulses FuelUsed 0.2192 lbm FuelRemain 99.0504 lbm FinalSCMass 1333.310 lbm ACE will cross the ecliptic plane 4/29/2015. This maneuver and the next maneuver are longer than usual because the spacecraft attitude will change from pointing below the ecliptic plane to pointing above the ecliptic plane. The longer maneuver likely expelled some trapped nitrogen and maneuver performance is slightly below the recent average (-3% versus better than -2%). The next maneuver is scheduled for Tuesday 4/21/2015. ======================================================================== OCRs: None ======================================================================== Activities: Data Capture: 99.990% DOY 095-102 2015 DOY 098 08:24:09-08:24:39 31 second gap SSR full & failover DOY 101 12:34:15-12:34:42 28 second gap while catching up on data Data playback had been behind schedule due to lost passes on DOY 097 & DOY 098 (see previous report). ======================================================================== Anomalies: DOY 102 04/12/2015 S-ACE-0523 S10-0007 Increase in SBE_CT_B SSR B Single Bit Error Count (SBE_CT_B) increased from 14066 to 14206 sometime between 04/05/2014 and 04/12/2015. SBE_CT is tracked as a measure of SSR health. IMPACT: Minimal. Single Bit Errors are automatically corrected by the SSR. No non-correctable errors (Hard Single Bit Errors & Double Bit Errors) have occurred throughout the mission. SBE_CT_A SBE_CT_B 1999 15 2000 2001 2002 2003 270 286 2004 858 2005 2006 2118 2007 510 3238 2008 4533 2009 525 6839 2010 780 7339 2011 10995 2012 13302 2013 2014 14066 2015 14206