New Horizons and the Onset of the Pioneer Anomaly

TL;DR

This paper discusses the Pioneer anomaly, an unexplained constant acceleration observed in spacecraft data, and suggests that data from the New Horizons mission could help determine if the anomaly's onset is related to distance from the Sun.

Contribution

It proposes using New Horizons data to test whether the Pioneer anomaly's onset correlates with distance from the Sun, potentially revealing new physics.

Findings

Detection of an unexplained acceleration in Pioneer data

Indication of anomaly onset near Saturn

Proposal for New Horizons to test the anomaly

Abstract

Analysis of the radio tracking data from the Pioneer 10/11 spacecraft at distances between about 20 - 70 AU from the Sun has indicated the presence of an unmodeled, small, constant, Doppler blue shift which can be interpreted as a constant acceleration of a_P= (8.74 \pm 1.33) \times 10^{-8} cm/s^2 directed approximately towards the Sun. In addition, there is early (roughly modeled) data from as close in as 5 AU which indicates there may have been an onset of the anomaly near Saturn. We observe that the data now arriving from the New Horizons mission to Pluto and the Kuiper Belt could allow a relatively easy, direct experimental test of whether this onset is associated with distance from the Sun (being, for example, an effect of drag on dark matter). We strongly urge that this test be done.