Exploring the Effects of Radiation Pressure on Orbiting Mirrors

Satellites around exoplanets would change the light curve of a transiting exoplanet, potentially providing evidence for extraterrestrial civilizations. These could be large, thin, lightweight mirrors used to redirect sunlight from a star to the surface of a planet. The feasibility and fuel efficiency of such an undertaking depends heavily on the effects of radiation pressure (RP). We simulated those satellites using REBOUND (Rein and Liu 2012), an N-body simulator, to understand the effect of RP on mirrors orbiting potentially habitable exoplanets. We varied the star type, initial semi-major axis, eccentricity, and other mirror orbital elements, and ran all simulations to crash, escape, or 1000 orbits. In some simulations RP affected the mirror throughout its orbit, while in others RP only affected the mirror when it was on the planet's night side. We compared these with simulations involving only gravitational effects. We compiled survival times and plotted orbital properties versus time to identify somewhat stable orbits. We are still investigating potentially stable configurations and analyzing data to decide whether full simulations need to be run in order to know a simulation's end state or if it shows in early trends.