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GR: Fachverband Gravitation und Relativitätstheorie

GR 22: Experimentelle Tests

GR 22.2: Vortrag

Freitag, 2. März 2012, 15:40–16:00, ZHG 002

Thermal recoil analysis of the Pioneer 10 spacecraft — •Benny Rievers and Claus Lämmerzahl — Centre of Applied Space Technology and Microgravity (ZARM), University of Bremen

Since the upcoming of investigations of the so called Pioneer Anomaly (PA), a constant unexplained residual Doppler shift of the deep space probes Pioneer 10 and Pioneer 11, many theories on the origin of the effect have been proposed and tested without success. It has soon be suggested to investigate the thermal effects, since only a small fraction of the available thermal energy is sufficient to cause a recoil in the magnitude of the anomaly. However, the constancy of the effect and simple model calculations seemed to contradict a thermal source. At the Centre of Applied Space Technology and Microgravity (ZARM) new high precision modeling methods for the assessment of thermal recoils acting on spacecraft have now been developed and utilized for a detailed thermal analysis of the complete Pioneer 10 mission. The analysis, which includes the detailed interior and exterior configuration of the craft as well as the available telemetry data shows that the observed residual effect can completely be reconstructed as a thermal recoil resulting from anisotropic heat radiation. For one part of the mission this result has already been confirmed independently and new analysis of longer Doppler data sets by NASA also favour a thermal explanation of the PA. In the talk, the modelling methods based on Finite Elements and raytracing as well as the robustness of the results will be discussed in detail.