Changing software philosophy for ACIS operations as Chandra ages

摘要

The Chandra X-Ray Observatory is about to start its 10th year of operations. Over the time of the mission, the Science Operations Team, ACIS (Advanced CCD Imaging Spectrometer) Operations group, has participated in spacecraft command load reviews. These reviews ensure the spacecraft commanding is safe for the instrument and the ACIS configuration matches the planned observation. The effectiveness of spacecraft command load reviews for ACIS depends on the ability to adapt the software as operations change in response to the aging of the spacecraft.rnWe have recently rewritten this software to start incorporating other spacecraft subsystems, including maneuvers and hardware commanding, to ensure the safety of ACIS. In addition, operational changes that optimize the science return of the spacecraft have created new constraints on commanding.rnThis paper discusses the reorganization of the code and the multiple changes to the philosophy of the code. The result is stronger, more flexible software that will continue to assist us in protecting ACIS throughout the Chandra mission.