Abstract

Contributed Talk - Splinter ExoPlanets

Polarimetry of Exoplanet-Exomoon Systems

M. B. Michaelis, M. Lietzow-Sinjen, S. Wolf
Christian-Albrechts-Universität zu Kiel, Institut für Theoretische und Astrophysik

Using the three-dimensional Monte Carlo radiative transfer code POLARIS, we investigated the potential of high-precision polarimetry for detecting and characterizing exoplanet–exomoon systems. The polarization phase curves exhibit distinct and significant variations resulting from mutual transits and shadowing events, which strongly depend on the inclination of the exomoon's orbit. Assuming the planet–satellite pair is spatially resolved from the host star, the transit of the exomoon across the center of the exoplanet can increase the degree of polarization by up to 2.7% in an Earth–Moon-like system near quadrature. In contrast, if the exomoon orbit is inclined such that it transits the planet off-center at the same phase angles, the polarization change is less than 0.5%. These findings suggest that polarimetric observations can provide valuable constraints on the orbital inclination of exomoons.