An investigation of chaotic planetary dynamics induced by the wide stellar binary companion to Boyajian’s Star

Boyajian’s Star (aka Tabby’s Star, aka KIC 8462852 A) has been the subject of intense research and intriguing theories since its enigmatic Kepler transit light curve was published in Boyajian et al. 2016. Today, several ideas remain plausible to explain the aperiodic, uniquely deep transits and long-term dimming trend, yet none satisfactorily fully explain the observed light curve. In Pearce et al. 2021, we showed that Boyajian’s Star has a wide stellar binary companion, KIC 8462852 B (ρ = 880 AU, M = 0.44 ± 0.02 Msun). While it is unlikely to be directly affecting the observed light curve of KIC 8462852 A, the wide secondary will likely have influenced the dynamics and evolution of the planetary environment around the primary. In this work, we use the orbital dynamics code REBOUND to model the KIC 8462852 AB system under the influence of the galactic potential, stellar flybys, and the presence of a giant planet around the primary, to investigate the possibility of orbital chaos induced in the system. If chaotic orbits around the primary are relatively common in our simulations, the wide binary could be a contributing factor to the unusual light curve through disruption of the orbits of smaller planetary bodies.