Aiming strategies for quarantined multiplanet missions

An important flight path constraint for current and future interplanetary missions arises from planetary quarantine restrictions. Each planet is assigned a maximum allowable probability of contamination which must not be violated. A portion of this probability is suballocated among the trajectory correction maneuvers. The remaining portion is allocated to the small ejecta/efflux sources released from the spacecraft that could possibly reach the planetary atmsophere and surface. For each maneuver, the suballocation is translated into an allowable probability of planetary impact. At the time of making a maneuver, the allowable probability of impact may dictate biasing the aim point. This study describes the technique of determining preferred biased aim points, given the suballocated probability of contamination for each maneuver.