Chameleon effect and the Pioneer anomaly

Abstract

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 acceleration than a large compact body, such as a planet, having a thin shell. The chameleon effect seems to present a natural way to explain the differences seen in deviations from pure Newtonian gravity for a spacecraft and for a planet, and appears to be compatible with the basic features of the Pioneer anomaly, including the appearance of a jerk term. However, estimates of the size of the chameleon effect indicate that its contribution to the anomalous acceleration is negligible. We conclude that any inverse-square component in the anomalous acceleration is more likely caused by an unmodelled reaction force from solar-radiation pressure, rather than a chameleon field effect.

16 pages; to appear in Phys.Rev.D

References in corpus (8)

• Chameleon Fields: Awaiting Surprises for Tests of Gravity in Space
• Chameleon Cosmology
• Study of the anomalous acceleration of Pioneer 10 and 11
• Indication, from Pioneer 10/11, Galileo, and Ulysses Data, of an Apparent Anomalous, Weak, Long-Range Acceleration
• The Pioneer Anomaly
• High precision thermal modeling of complex systems with application to the flyby and Pioneer anomaly
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• Combined cosmological and solar system constraints on chameleon mechanism

Cited by in corpus (5)

• Gravitational Anomalies in the Solar System?
• 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
• The Pioneer Anomaly: an inconvenient reality or NASA's 12 year misconception?
• Chameleon gravity and satellite geodesy