MRO's Evolving Process for Science Planning

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[Abstract] The Mars Reconnaissance Orbiter (MRO) began Primary Science Phase (PSP) mapping operations on November 8, 2006. It carries six science instruments, with differing requirements for repetitive global monitoring, regional or global survey mapping, and/or targeted observations of Mars. While some instruments require nadir-oriented operations, others take frequent off-nadir observations (especially for stereo viewing). Since four instruments share a common boresight, the operations requirements of these six experiments are often incompatible; thus the science planning process is interactive. This process is by necessity more complex than in some recent NASA Mars missions, but it is far less time-consuming (and more repetitive) than processes used by many large planetary missions. It takes full advantage of MRO’s novel onboard processing capabilities, and uses simple electronic file exchange between widely distributed Science Teams. This paper describes the process used to plan and schedule observations of Mars, with a special emphasis on lessons learned and modifications made since PSP began. A “waterfall” process is used to schedule decreasingly interactive activities on MRO. First, a Background Sequence of spacecraft activities (e.g. orbital trim maneuvers) is generated. This becomes the background against which MRO’s Science Teams, acting together every second Monday as the Target Acquisition Group (TAG), schedule two weeks of the highest-priority observations (“Must-Haves”) and the orbits reserved for nadir survey observations. Following this, three teams (CRISM, HiRISE, and CTX) propose off-nadir observations for a two-week science sequence. These interactive observations (IOs) are specified by latitude, longitude, and orbit. A priority-driven round-robin procedure is used to schedule IOs on that Friday, a week before the beginning of the two-week sequence. Exact timing is not needed for this scheduling activity, because MRO uses onboard targeting software to determine when to slew toward a target and shutter an instrument, using an onboard ephemeris. Finally, each week, MRO’s science teams schedule one week of non-interactive observations (NIOs) that don’t conflict with the scheduled Must-Haves and IOs.