SOT Shift Report 2009-08-28 L3688 (retroactive)

This retroactive report (from Mike Juda's e-mail) gives a brief description of AUG2609
load stoppage event on August 28, 2009

August 28, 2009 2:32 PM local time:

 
At the comm pass at 0750-1125z Chandra was not in its expected configuration based on the 
AUG2609A load products; it had not maneuvered to the expected gravity-gradient attitude 
and ACIS was still performing a CTI measurement.

The procedure SOP_61020_RADBELT_ENTRY was executed to finish preparing ACIS for the 
radiation zone entry (stop science & power down the video boards). The running load 
segments in SCS 130 and 128 were terminated to prevent unwanted commands from 
being issued. The contents of SCS 130, which should have been in control at the time, 
were dumped and verified to not be from the AUG2609A products.

Chandra is in a radiation safe configuration and at an attitude that is good until day 245.

A replan schedule (AUG2909) that includes the remainder of this week and the schedule for 
next week are currently in work and should resume the science program at 2009:241:02:00 UT

Ground procedures will be modified to prevent a re-occurrence of this issue.