Related papers: Pioneer's Final Riddle
Recently, Anderson et al. presented possible evidence for an anomalous acceleration acting on spacecrafts. Furthermore, the motions of several planets and comets are known to experience unexplained disturbances. A transneptunian comet or…
The possibility that the apparent anomalous acceleration of the Pioneer 10 and 11 spacecraft may be due, at least in part, to a chameleon field effect is examined. A small spacecraft, with no thin shell, can have a more pronounced anomalous…
This paper proposes an explanation for the Pioneer anomaly: an unexplained Sunward acceleration of 8.74 +/- 1.33 x 10^-10 m s^-2 seen in the behaviour of the Pioneer probes. Two hypotheses are made: (1) Inertia is a reaction to Unruh…
Independently developed orbit determination software is used to analyze the orbits of Pioneer 10 and 11 using Doppler data. The analysis takes into account the gravitational fields of the Sun and planets using the latest JPL ephemerides,…
In a previous work we showed that massive test particles exhibit a non-geodesic acceleration in a modified theory of gravity obtained by a non-commutative deformation of General Relativity (so-called Matrix Gravity). We propose that this…
Pioneer 10 and 11 were the first probes sent to study the outer planets of the Solar System and Pioneer 10 was the first spacecraft to leave the Solar System. Besides their already epic journeys, Pioneer 10 and 11 spacecraft were subjected…
Turyshev, S.G., Toth, V.T., 2009. (preprint arXiv:0906.0399) reported on the status of the analysis of recently recovered Pioneer 10 (P10) and Pioneer 11 (P11) flight data and commented on some, but not all, of the characteristics of the…
Applying Newtonian dynamics in five dimensions rather than four, to a universe that is closed, isotropic and expanding,suggests that under certain circumstances an additional and previously unidentified acceleration, a_A, can arise…
In order to satisfy the equivalence principle, any non-conventional mechanism proposed to gravitationally explain the Pioneer anomaly, in the form in which it is presently known from the so-far analyzed Pioneer 10/11 data, cannot leave out…
The flyby anomaly is a persistent riddle in astrodynamics. Orbital analysis in several flybys of the Earth since the Galileo spacecraft flyby of the Earth in 1990 have shown that the asymptotic post-encounter velocity exhibits a difference…
In this paper we test the hypothesis that the Pioneer anomaly can be of gravitational origin by comparing the predicted model-independent shifts Delta a/a for the semimajor axis of Uranus and Neptune with the Voyager 2 radio-technical…
The anomalous acceleration of Pioneer 10 is presented as a calculation using a simple optical model. The model is based on the bending of background gravity behind the Sun in the same way that light is bent by the Sun. Structures of…
A collection is made of presently unexplained phenomena within our Solar system and in the universe. These phenomena are (i) the Pioneer anomaly, (ii) the flyby anomaly, (iii) the increase of the Astronomical Unit, (iv) the quadrupole and…
A conventional explanation of the correlation between the Pioneer 10/11 anomalous acceleration and spin-rate change is given. First, the rotational Doppler shift analysis is improved. Finally, a relation between the radio beam reaction…
In March 2008 anomalous behavior in spacecraft flybys of Earth was reported in Physical Review Letters, Volume 100, Issue 9, March 7, 2008, in an article entitled "Anomalous Orbital-Energy Changes Observed during Spacecraft Flybys of…
A relativistic theory is proposed to explain the anomalous accelerations of Pioneer 10/11, Galileo and Ulysses spacecrafts. The theory points out at the limitations of the weak field approximation and proposes a drift in the proper time of…
We examine the Pioneer anomaly - a reported anomalous acceleration affecting the Pioneer 10/11, Galileo and Ulysses spacecrafts - in the context of a braneworld scenario. We show that effects due to the radion field cannot account for the…
The Nonsymmetric Kaluza-Klein (Jordan-Thiry) Theory leads to a model of a modified acceleration that can fit an anomalous acceleration experienced by the Pioneer 10 and 11 spacecraft. The future positions of those spacecrafts are predicted…
Recently we reported that radio Doppler data generated by NASA's Deep Space Network (DSN) from the Pioneer 10 and 11 spacecraft indicate an apparent anomalous, constant, spacecraft acceleration with a magnitude $\sim 8.5\times 10^{-8}$ cm…
A few observational and/or experimental results have dramatically pushed forward the research program on gravity as those from the radio-metric Doppler tracking received from the Pioneer 10 and 11 spacecrafts when the space vehicles were at…