Sun Flux Variations Due to orbiting planets: The solar system as a Non-Compact Planetary System
2020-06-30
H. Barbier, E. López, B. Tipán, C. Vásconez
We study the photometric phase curves for the planets of our solar system which can be
considered as a prototypical non-compact planetary system. We focus on modeling the small variations
caused by three effects: reflection, ellipsoidal, and Doppler beaming. Theoretical predictions for these
photometric variations are proposed, considering a hypothetical external observer. Unlike similar studies
of multi-planetary systems, the physical and geometrical parameters for each planet of the solar system
are well-known. Therefore, we can accurately evaluate the relationships that shape the planetary light
curves for a fictitious external observer. Our results suggest that, for all planets, the ellipsoidal effect is
very weak while the Doppler beaming effect (DBE) is, in general, dominant. In fact, the DBE seems to
be the principal cause of variations of the light curves for the planets of the solar system. However, for
Mercury and Venus the Doppler beaming and reflection effects have similar amplitudes. The phase curves
obtained for the planets of the solar system show new interesting features of interest for the study of other
non-compact planetary systems