Modelling the flyby anomalies using a modification of inertia

Abstract

The flyby anomalies are unexplained velocity jumps of 3.9, -4.6, 13.5, -2, 1.8 and 0.02 mm/s observed near closest approach during the Earth flybys of six spacecraft. These flybys are modelled here using a theory that assumes that inertia is due to a form of Unruh radiation, and varies with acceleration due to a Hubble-scale Casimir effect. Considering the acceleration of the craft relative to every particle of the rotating Earth, the theory predicts that there is a slight reduction in inertial mass with increasing latitude for an unbound craft, since near the pole it sees a lower average relative acceleration. Applying this theory to the in- and out-bound flyby paths, with conservation of momentum, the predicted anomalies were 2.9, -0.9, 20.1, 0.9, 3.2 and -1.3 mm/s. Three of the flyby anomalies were reproduced within error bars, and the theory explains their recently-observed dependence on the latitude difference between their incident and exit trajectories. The errors for the other three flybys were between 1 and 3 mm/s.