Résumé / Abstract Seminaire_GReCO

"The Study of the Anomalous Accelerations of the Pioneer 10 and 11 Spacecraft"

Slava Turyshev
Jet Propulsion Lab. (JPL), California Inst. Technology (Caltech) (Pasadena, California, Etats-Unis d'Amérique)

Analysis of radio-metric tracking data from the Pioneer 10 and 11 spacecraft received from the distances between 20-70 astronomical units (AU) from the Sun has consistently indicated the presence of an anomalous, small, constant Doppler frequency drift. The drift can be interpreted as being due to a constant acceleration of $a_P = (8.74 \pm 1.33) 10^{-8} cm/s^2$ directed towards the Sun. Although it is suspected that there is a systematic origin to the effect, none has been found. As a result, the nature of this anomaly has become of growing interest. We will discuss the details of this recent investigation focusing on effects both external to and internal to the spacecraft, as well as those due to modeling and computational techniques. We will summarize our current knowledge of the conditions led to observation of the anomalous acceleration on the Pioneer spacecraft. We review some of the mechanisms proposed to explain the anomaly and show their inability to account for the magnitude and observed behavior of the discovered anomaly.

lundi 6 juin 2005 - 11:00
Salle des séminaires Évry Schatzman,
Institut d'Astrophysique de Paris

Page web du séminaire / Seminar's webpage