Reconstruction of Earth Flyby by the Juno Spacecraft

The Juno spacecraft conducted a successful gravity-assist flyby of the Earth on 09 October 2013, putting the spacecraft on a trajectory to reach Jupiter in July 2016. The DSN tracking was supplemented by tracking from two ESA stations, giving us an unprecedented, near continuous level of tracking for an interplanetary spacecraft flyby of Earth. We discuss the process of reconstructing that trajectory, the challenges encountered in that effort, and the results. In particular, no anomalous velocity change was observed at or near perigee as has been observed in some of the previous Earth gravity assist flybys by other spacecraft.