Solar Radiation Pressure and Deviations from Keplerian Orbits

TL;DR

This paper investigates how solar radiation pressure combined with relativistic effects causes deviations from Keplerian orbits for solar sail satellites, revealing measurable impacts on orbital periods and potential for detecting subtle spacetime phenomena.

Contribution

It introduces a comprehensive analysis of how solar radiation pressure modifies orbital dynamics, including effects of spacetime curvature, solar oblateness, and other relativistic factors.

Findings

Solar radiation pressure decreases effective solar mass, increasing orbital period.

Radiation pressure enhances relativistic effects, making some deviations detectable.

Multiple relativistic effects contribute to deviations from Kepler's law in solar sail orbits.

Abstract

Newtonian gravity and general relativity give exactly the same expression for the period of an object in circular orbit around a static central mass. However, when the effects of the curvature of spacetime and solar radiation pressure are considered simultaneously for a solar sail propelled satellite, there is a deviation from Kepler's third law. It is shown that solar radiation pressure affects the period of this satellite in two ways: by effectively decreasing the solar mass, thereby increasing the period, and by enhancing the effects of other phenomena, rendering some of them detectable. In particular, we consider deviations from Keplerian orbits due to spacetime curvature, frame dragging from the rotation of the sun, the oblateness of the sun, a possible net electric charge of the sun, and a very small positive cosmological constant.