Proceedings Article | 12 July 2008
Proc. SPIE. 7016, Observatory Operations: Strategies, Processes, and Systems II
KEYWORDS: Observatories, Safety, Sun, Stars, Sensors, X-rays, Silicon, Space telescopes, Space operations, X-ray telescopes
Scheduling observatory time to maximize both day-to-day science target integration time and the lifetime
of the observatory is a formidable challenge. Furthermore, it is not a static problem. Of course, every
schedule brings a new set of observations, but the boundaries of the problem change as well. As
spacecraft ages, its capabilities may degrade. As in-flight experience grows, capabilities may expand. As
observing programs are completed, the needs and expectations of the science community may evolve.
Changes such as these impact the rules by which a mission scheduled. In eight years on orbit, the Chandra
X-Ray Observatory Mission Planning process has adapted to meet the challenge of maximizing day-to-day
and mission lifetime science return, despite a consistently evolving set of scheduling constraints. The
success of the planning team has been achieved, not through the use of complex algorithms and
optimization routines, but through processes and home grown tools that help individuals make smart short
term and long term Mission Planning decisions. This paper walks through the processes and tools used to
plan and produce mission schedules for the Chandra X-Ray Observatory. Nominal planning and
scheduling, target of opportunity response, and recovery from on-board autonomous safing actions are all
addressed. Evolution of tools and processes, best practices, and lessons learned are highlighted along the
way.
