Collaborative risk management for the Cassini-Huygens probe mission

Cassini-Huygens is an internationally cooperative mission between the National Aeronautics and Space Administration (NASA), the European Space Agency (ESA) and Agenzia Spaziale Italiana (ASI) to study Saturn, its rings, moons, icy satellites and magnetosphere. The spacecraft will release Huygens on December 24, 2004, setting up the correct entry conditions for the probe's arrival during Cassini's third flyby of Titan. Huygens will then coast for 20 days while the Cassini spacecraft continues on overhead, awaiting news of its arrival. Upon arrival at Titan, Huygens will "wake up" to analyze the composition of the atmosphere and conduct unprecedented observations of this distant world as it descends through the clouds. Deep space missions, such as Cassini-Huygens, are inherently risky. There are numerous risks that could threaten or prematurely end the mission. An effective risk management process was established at the Jet Propulsion Laboratory (JPL) to address risk to the Cassini spacecraft and mission as a whole. Early on, it became evident that the risk management effort at JPL was focused on the orbiter and the orbiter-to-probe interface. ESA quickly responded by establishing a risk management effort of its own, to address risks specific to the Huygens probe and its suite of instruments. With both agencies actively addressing risk management, the next logical step was to integrate the two processes into one comprehensive approach. It is through this international, collaborative risk management effort that the Cassini-Huygens program is able to proactively identify, assess and manage risk to the mission. This paper describes the collaborative risk management approach implemented by the Cassini-Huygens team.