ar X iv : a st ro - p h / 06 12 56 7 v 1 2 0 D ec 2 00 6 Scalar potential model of the Pioneer Anomaly

The unexplained sunward acceleration aP of the Pioneer 10 (P10) and the Pioneer 11 (P11) spacecraft remains a mystery. A scalar potential model (SPM) that derived from considerations of galaxy clusters, of red-shift, and of HI rotation curves of spiral galaxies is applied to the Pioneer Anomaly. Matter is posited to warp the scalar potential ρ field. The gradient of the ρ field produces a force on matter and light. The changing ρ along the light path causes the Pioneer Anomaly. The SPM is consistent with the general value of aP, with the annual periodicity, with the differing aP between the spacecraft, with the slowly declining aP, with the low value of aP immediately before the P11's Saturn encounter, with the high uncertainty in the value of aP obtained during and after the P11's Saturn encounter, and with the cosmological connection suggested by aP ≈ cHo. The effect of the ρ field warp appears as the curvature of space proposed by general relativity.