How Well Do We Know the Orbits of the Outer Planets?

Abstract

This paper deals with the problem of astrometric determination of the orbital elements of the outer planets, in particular by assessing the ability of astrometric observations to detect perturbations of the sort expected from the Pioneer effect or other small perturbations to gravity. We also show that while using simplified models of the dynamics can lead to some insights, one must be careful to not over-simplify the issues involved lest one be misled by the analysis onto false paths. Specifically, we show that the current ephemeris of Pluto does not preclude the existence of the Pioneer effect. We show that the orbit of Pluto is simply not well enough characterized at present to make such an assertion. A number of misunderstandings related to these topics have now propagated through the literature and have been used as a basis for drawing conclusions about the dynamics of the solar system. Thus, the objective of this paper is to address these issues. Finally, we offer some comments dealing with the complex topic of model selection and comparison.

Accepted for publication in the ApJ

References in corpus (9)

• Dark matter vs. modifications of the gravitational inverse-square law. Results from planetary motion in the solar system
• The modified Newtonian dynamics-MOND-and its implications for new physics
• Solar system constraints on multi-field theories of modified dynamics
• Could the Pioneer anomaly have a gravitational origin?
• Testing Gravity in the Outer Solar System: Results from Trans-Neptunian Objects
• Radar ranging and Doppler tracking in post-Einsteinian metric theories of gravity
• Density of dark matter in Solar system and perihelion precession of planets
• Nonlinear electrodynamics and the Pioneer 10/11 spacecraft anomaly
• Possible relation between galactic flat rotational curves and the Pioneers' anomalous acceleration

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• Can observations inside the Solar System reveal the gravitational properties of the quantum vacuum?
• Conformal Cosmology and the Pioneer Anomaly
• On the vacuum fluctuations, Pioneer Anomaly and Modified Newtonian Dynamics
• Re-Examination of Globally Flat Space-Time
• Does the Neptunian system of satellites challenge a gravitational origin for the Pioneer anomaly?
• Pioneer 10 and 11 Spacecraft Anomalous Acceleration in the light of the Nonsymmetric Kaluza-Klein (Jordan-Thiry) Theory
• On the possible onset of the Pioneer anomaly