Related papers: Astrometric Solar-System Anomalies
More than 635 000 positional observations (mostly radiotechnical) of planets and spacecraft (1961-2010), have been used for estimating possible changes of the gravitation constant, the solar mass, and semi-major axes of planets, as well as…
The improvements of the observations of the solar system allowed by the use of probes and big instruments let appear several problems: The frequencies of the radio signals received from the probes sent over 5 UA from the Sun are too high;…
Possible explanations of the recently reported anomalous increase of the eccentricity of the lunar orbit are sought in terms of classical Newtonian mechanics, general relativity, and long-range modifications of gravity.
Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a…
The inverse square law of gravity is poorly probed by experimental tests at distances of ~ 10 AUs. Recent analysis of the trajectory of the Pioneer 10 and 11 spacecraft have shown an unmodeled acceleration directed toward the Sun which was…
All four giant planets in the Solar system possess irregular satellites, characterized by large, highly eccentric and/or inclined orbits that are distinct from the nearly circular, uninclined orbits of the regular satellites. This…
We propose here an explanation of the Pioneer anomaly which is not in conflict with the cartography of the solar system. In our model, the spaceship does not suffer any extra acceleration but follows the trajectory predicted by standard…
A time-dependent model of space-time is used to suggest simple explanations for the increasing of the Astronomical unit, as well as the increasing of the distance from the Earth to the Moon. The Pioneer anomaly is also considered.
We continue our exploration of whether the flyby anomalies can be explained by scattering of spacecraft nucleons from dark matter gravitationally bound to the earth, with the addition of data from five new flybys to that from the original…
It seems to be generally accepted that apparently anomalous cosmological observations, such as accelerating expansion, etc., necessarily are inconsistent with standard general relativity and standard matter sources. Following the…
Radiometric tracking data from Pioneer 10 and 11 spacecraft has consistently indicated the presence of a small, anomalous, Doppler frequency drift, uniformly changing with a rate of ~6 x 10^{-9} Hz/s; the drift can be interpreted as a…
A body in Solar orbit beyond the Kuiper belt exhibits an annual parallax that exceeds its apparent proper motion by up to many orders of magnitude. Apparent motion of this body along the parallactic ellipse will deflect the angular position…
The trajectories of test particles moving in the gravitational field of a non-spherically symmetric mass distribution become affected by the presence of multipole moments. In the case of hyperbolic trajectories, the quadrupole moment of an…
The Pioneer 10/11 spacecraft yielded the most precise navigation in deep space to date. However, their radio-metric tracking data received from the distances between 20--70 astronomical units from the Sun has consistently indicated the…
Astrometric detection of an unseen companion is based on analysis of apparent motion of its host star around the system's barycentre. Systems with orbital period close to one year may escape detection if orbital motion of their host stars…
Anderson, et al., find the measured trajectories of Pioneer 10 and 11 spacecraft deviate from the trajectories computed from known forces acting on them. This unmodelled acceleration can be accounted for by non-isotropic radiation of…
Astronomers occasionally detect an object having unexpected shape, unexplainable photometry, or unprecedented spectra that are inconsistent with our contemporary knowledge of the universe. Upon careful assessment, many of these anomalies…
In the context of a parametric theory (with the time being a dynamical variable) we consider the coupling between the quantum vacuum and the background gravitation that pervades the universe (unavoidable because of the universality of…
Analysis of radio-metric tracking data from the Pioneer 10/11 spacecraft at distances between 20 - 70 astronomical units (AU) from the Sun has consistently indicated the presence of an anomalous, small, constant Doppler frequency drift. The…
The reported anomalous acceleration of the Pioneer 10 spacecraft of -8.5X10^{-10} m/s^2 (i.e. towards the sun) can be explained by a gravitational interaction on the S-band signals traveling between Pioneer 10 and the earth. The effect of…