Earth and Moon encounters by the Galileo Jupiter orbiter

The Galileo Venus-Earth-Earth-Gravity-Assist trajectory to Jupiter is discussed. It includes two encounters from deep space with the Earth and the Earth-Moon system. Fortuitous and unique opportunities therefore exist to observe and study the Earth and Earth's moon during both of these encounters. Given the Galileo science payload, a candidate set of Earth and Moon science objectives is presented. The conditions and constraints of the Earth and Moon encounters, which define the observing opportunity, and which bound the objectives, are reviewed.