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The Cassini-Huygens mission to Saturn launched in October 1997. The Cassini Plasma Spectrometer (CAPS) is an in-situ instrument and is one of 12 instruments on the orbiter. Cruise science (beyond instrument checkout periods and periodic maintenance) was approved, and over 870 days of data were collected prior to the start of the prime mission. Prime mission operations started in January 2004 and continued through end of June 2008. Given the success of the Cassini mission at Saturn, an extended mission, the Equinox Mission, was approved for an additional two years, ending September 2010. The continuing success of the Equinox mission led to approval of a second extended mission called the Solstice Mission. The Solstice mission has approval through September 2012 with pending approval through July 2017. The Cassini Plasma Spectrometer (CAPS) has generated a wealth of science data and we have over 240 publications. In addition, the CAPS scientists participate in conferences, inter-team collaborations, and community outreach. Collection of data has not been without instrument related challenges. This paper will discuss a few of the in-flight instrument related anomalies experienced by CAPS including timing difference between the engineering model and the flight model, actuator related anomalies, and a latched bit. The analysis will cover how the anomalies were discovered, the techniques used to diagnose the problems in-flight, fixes that were implemented, how the anomalies affected operation of the instrument and collection of science, and lessons learned from the process.

The Cassini Plasma Spectrometer (CAPS) is one of twelve instruments on the Cassini-Huygens spacecraft. As the mission has progressed from launch, through Cruise, Tour, and Extended Mission, the level of automation within Operations and Data Processing has increased. As the Solstice Mission (2nd extended mission) has been approved, a move towards a final set of automated tools is in progress. This paper will address how automation has changed and what decisions were involved in the choice of the final set of automated tools to last through the Solstice Missions (into July 2017).1 2

Due to budget restrictions, the responsibility for operation of the science payload on the Cassini-Huygens mission is distributed across the science instrument teams12. Under this distributed operations model, each instrument site is responsible for uplink operations instead of the large, centrally located operations facilities that are typical of spacecraft missions. Additionally, instrument teams are responsible for the standard downlink operations, science, and archiving. As long as requirements and deadlines are met, the Cassini project does not dictate how the requirements are met. Each instrument team was left on its own to come up with how they would respond to this challenge. This paper will chronicle the specifics of how distributed operations are coordinated and run within the Cassini Plasma Spectrometer (CAPS) operations team. By critically examining how operations have evolved over the 10 year period from late 1998 through the end of 2008, this paper will discuss lessons learned in operating this complex instrument. Additionally, current management techniques will be examined to determine if the efficiency of distributed operations can be improved.