Correlations between planetary transit timing variations, transit duration variations and brightness fluctuations due to exomoons

Abstract

Modern theoretical estimates show that with the help of real equipment we are able to detect large satellites of exoplanets (about the size of the Ganymede), although, numerical attempts of direct exomoon detection were unsuccessful. Lots of methods for finding the satellites of exoplanets for various reasons have not yielded results. Some of the proposed methods are oriented on a more accurate telescopes than those exist today. In this work, we propose a method based on relationship between the transit timing variation (TTV) and the brightness fluctuations (BF) before and after the planetary transit. With the help of a numerical simulation of the Earth-Moon system transits, we have constructed data on the BF and the TTV for any configuration of an individual transit. The experimental charts obtained indicate an easily detectable near linear dependence. Even with an artificial increase in orbital speed of the Moon and high-level errors in measurements the patterns suggest an accurate correlation. A significant advantage of the method is its convenience for multiple moons systems due to an additive properties of the TTV and the BF. Its also important that mean motion resonance (MMR) in system have no affect on ability of satellites detection. At the end we tried to retrieve parameters of the Moon (without additional satellites) on the basis of the simulated photometric curves. The results perform errors at the level of \(\approx 0.45\) for the mass and \(\approx 0.24\) for the radius with TTV measurements accuracy =60s and Kepler-like noise for photometry.