A possible flyby anomaly for Juno at Jupiter

Abstract

In the last decades there have been an increasing interest in improving the accuracy of spacecraft navigation and trajectory data. In the course of this plan some anomalies have been found that cannot, in principle, be explained in the context of the most accurate orbital models including all known effects from classical dynamics and general relativity. Of particular interest for its puzzling nature, and the lack of any accepted explanation for the moment, is the flyby anomaly discovered in some spacecraft flybys of the Earth over the course of twenty years. This anomaly manifest itself as the impossibility of matching the pre and post-encounter Doppler tracking and ranging data within a single orbit but, on the contrary, a difference of a few mm/s in the asymptotic velocities is required to perform the fitting.Nevertheless, no dedicated missions have been carried out to elucidate the origin of this phenomenon with the objective either of revising our understanding of gravity or to improve the accuracy of spacecraft Doppler tracking by revealing a conventional origin.With the occasion of the Juno mission arrival at Jupiter and the close flybys of this planet, that are currently been performed, we have developed an orbital model suited to the time window close to the * E-mail: luiacrod@imm.upv.es 1 perijove. This model shows that an anomalous acceleration of a few mm/s 2 is also present in this case. The chance for overlooked conventional or possible unconventional explanations is discussed.

Impact Models of Gravitational and Electrostatic Forces

“…Juno was inserted into an elliptical orbit around Jupiter on 4 July 2016 with an orbital period of 53.5 days. Acedo et al [74] studied the first and the third orbit with a periapsis of "4200 km over the planet top clouds". "A significant radial component was found and this decays with the distance to the center of Jupiter as expected from an unknown physical interaction … .…”

Geometry of numbers and dimensionality

“…A non-integer, irrational number for dimensionality has implications not only in study of complex system behavior (as in [9]) but also for aerospace engineering, as in improving spacecraft navigation and trajectory data [14], as well in physics [10] and the study of cosmology. I do not wish to revisit the implications already discussed in the previous papers, but here I consider relevance to a much-discussed problem related to estimates of the Hubble constant.…”