SearcharxivSearch

arXiv subjects

Hans-Juergen Busack

Publications and source records attributed to Hans-Juergen Busack.

2 recordsLinked to original sources

Test for consistence of a flyby anomaly simulation with the observed Doppler residuals for the Messenger flybys of Mercury

In 2007, the observed Earth flyby anomalies have been successfully simulated using an empirical formula (H. J. Busack, 2007). This simulation has led to the prediction of anomaly values, to be expected for the Rosetta flybys of Mars in 2007, and following twice of Earth in 2007 and 2009. While the data for the Mars flyby are yet under evaluation, the predictions of the formula for the last two Earth flybys of Rosetta are fully confirmed now. This is remarkable, since an alternatively proposed formula (Anderson et al., 2007) failed to predict the correct values for the recent flybys. For the Mercury flybys of the Messenger spacecraft, this alternative formula predicts a null result. In the meantime, Doppler residuals of these flybys on 14.01.2008 and 06.10.2008 are availabel. On both flybys, significant residuals were observed, using gravity data derived by Mariner 10 on Mercury (D. E. Smith et al., 2009). According to the authors, these residuals cannot be eliminated totally by adjustment of the second degree gravity coefficients and by assumption of irregular mass concentrations of acceptable value on Mercury. In this investigation, I adapt the output of the simulation program to compare with the measured Doppler residuals of the Mercury flybys without changing the formerly derived parameters for the Earth flybys. The simulation with these parameters leads to Doppler residuals of the Mercury flybys compatible with the measured curves. Additionally, the expected flyby anomalies are calculated. Since the gravity field of Mercury is not explored yet with sufficient accuracy, this result cannot be falsified or confirmed until the evaluation of the coming Mercury orbits of Messenger will be finished. If the proposed empirical formula would be confirmed then again, this would be a strong indication of an underlying physical reality.

physics.gen-ph

Simulation of the flyby anomaly by means of an empirical asymmetric gravitational field with definite spatial orientation

All anomalous velocity increases until now observed during the Earth flybys of the spacecrafts Galileo, NEAR, Rosetta, Cassini and Messenger have been correctly calculated by computer simulation using an asymmetric field term in addition to the Newtonian gravitational field. The specific characteristic of this term is the lack of coupling to the rotation of the Earth or to the direction of other gravitational sources such as the Sun or Moon. Instead, the asymmetry is oriented in the direction of the Earth's motion within an assumed unique reference frame. With this assumption, the simulation results of the Earth flybys Galileo1, NEAR, Rosetta1 and Cassini hit the observed nominal values, while for the flybys Galileo2 and Messenger, which for different reasons are measured with uncertain anomaly values, the simulated anomalies are within plausible ranges. Furthermore, the shape of the simulated anomaly curve is in qualitative agreement with the measured Doppler residuals immediately following the perigee of the first Earth flyby of Galileo. Based on the simulation, an estimation is made for possible anomalies of the recently carried out flybys of Rosetta at Mars on 25.02.07 and at the Earth on 13.11.07, and for the forthcoming Earth flyby on 13.11.09. It is discussed, why a so modelled gravitational field has not been discovered until now by analysis of the orbits of Earth satellites, and what consequences are to be considered with respect to General Relativity.

physics.gen-ph