Abstract

Anomalous Pioneer 10/11 radio metric data indicate an apparent, constant skewing between predicted and observed Doppler shifts. This indicates a possible acceleration of 8.5 X 10-8 cm/s2 toward the Sun for both craft. Gravitometric models and systemic problems fail to explain the discrepancy. The anomalous signals, fully accountable in Galilean modeling, seem to indicate an error in the relativistic Doppler equations rather than any new physics. The Space Interferometry Mission (SIM), due for launch by NASA in 2007, will be able to determine directly whether length contraction (as introduced by the Earth's changing motion with respect to the stars) exists. With a resolution of 1 microarcsecond per degree, its resolution far exceeds the expected relativistic effect of +/-18 microarcseconds per degree. This project represents the first direct test of relativistic length contraction" in 100 years since that theories introduction.