Modelling the reflective thermal contribution to the acceleration of the Pioneer spacecraft

TL;DR

This paper introduces an enhanced method for calculating the thermal acceleration of Pioneer spacecraft by considering diffusive and specular reflections, providing more reliable estimates of their thermal contributions over time.

Contribution

It presents a novel, improved computational approach for radiative momentum transfer that accounts for both types of reflection, refining previous models of spacecraft thermal acceleration.

Findings

Confirmed previous estimates of thermal acceleration.

Provided bounds for acceleration and its temporal evolution.

Enhanced the reliability of thermal modeling for deep-space probes.

Abstract

We present an improved method to compute the radiative momentum transfer in the Pioneer 10 & 11 spacecraft that takes into account both diffusive and specular reflection. The method allows for more reliable results regarding the thermal acceleration of the deep-space probes, confirming previous findings. A parametric analysis is performed in order to set an upper and lower-bound for the thermal acceleration and its evolution with time.