Related papers: Using Early Data to Illuminate the Pioneer Anomaly

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,…

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…

A previous paper [1] introduced a quantum-mechanical theory of gravity, and showed it agrees with the standard experimental tests of general relativity. Doppler tracking signals returned by the Pioneer 10 and 11 space probes offer an…

From Doppler tracking data and data on circular motion of astronomical objects we obtain a metric of the Pioneer Anomaly. The metric resolves the issue of manifest absence of anomaly acceleration in orbits of the outer planets and…

There are at least four unexplained anomalies connected with astrometric data. Perhaps the most disturbing is the fact that when a spacecraft on a flyby trajectory approaches the Earth within 2000 km or less, it often experiences a change…

The nonsymmetric gravitational theory leads to a modified acceleration law that can at intermediate distance ranges account for the anomalous acceleration experienced by the Pioneer 10 and 11 spacecraft.

We explore the possibility that the observed onset of the Pioneer anomaly after Saturn encounter by Pioneer 11 is not necessarily due to mismodeling of solar radiation pressure but instead reflects a physically relevant characteristic of…

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…

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…

According to a recent modified model of gravity at large distances, a radial constant and uniform extra-acceleration A_Rin of Rindler type acts upon a test particle p in the static field of a central mass M if certain conditions are…

If the Pioneer anomaly has a gravitational origin, it would, according to the equivalence principle, distort the motions of the planets in the Solar System. Since no anomalous motion of the planets has been detected, it is generally…

According to the cosmological principle, the Universe should appear isotropic, without any preferred directions, to an observer whom we may consider to be fixed in the co-moving co-ordinate system of the expanding Universe. Such an observer…

Four different data sets pertaining to the neutral atom environment at 1 AU are presented and discussed. These data sets include neutral solar wind and interstellar neutral atom data from IMAGE/LENA, energetic hydrogen atom data from…

In this paper we analyze the impact on the orbital motions of the outer planets of the solar system from Jupiter to Pluto of some velocity-dependent forces recently proposed to phenomenologically explain the Pioneer anomaly, and compare…

A fully relativistic modified gravitational theory including a fifth force skew symmetric field is fitted to the Pioneer 10/11 anomalous acceleration. The theory allows for a variation with distance scales of the gravitational constant G,…

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…

We argue that the so-called "Pioneer Anomaly" is related to the quantum vacuum fluctuations. Our approach is based on the hypothesis of the gravitational repulsion between matter and antimatter, what allows considering, the virtual…

We report the serendipitous detection of a previously unreported pulsar from the direction of the Small Magellanic Cloud using data from the CHANDRA X-Ray Observatory. Because of the luminosity of about 1.5x10^35 ergs/s, its near lack of…

The reported anomalous acceleration acting on the Pioneers spacecrafts could be seen as a consequence of the existence of some local curvature in light geodesics when using the coordinate speed of light in an expanding space-time. The…

High-resolution spectropolarimetric observations of active region NOAA 11271 were obtained with the spectro-polarimeter on board Hinode to analyze the properties of an anomalous flow in the photosphere in a sunspot penumbra. We detect a…