Zusammenfassung
Kepler-56 is a multi-planet system containing two coplanar inner planets that
are in orbits misaligned with respect to the spin axis of the host star, and an
outer planet. Various mechanisms have been proposed to explain the broad
distribution of spin-orbit angles among exoplanets, and these theories fall
under two broad categories. The first is based on dynamical interactions in a
multi-body system, while the other assumes that disk migration is the driving
mechanism in planetary configuration and that the star (or disk) is titled with
respect to the planetary plane. Here we show that the large observed obliquity
of Kepler-56 system is consistent with a dynamical origin. In addition, we use
observations by Huber et al. (2013) to derive the obliquity's probability
distribution function, thus improving the constrained lower limit. The outer
planet may be the cause of the inner planets' large obliquities, and we give
the probability distribution function of its inclination, which depends on the
initial orbital configuration of the planetary system. We show that even in the
presence of precise measurement of the true obliquity, one cannot distinguish
the initial configurations. Finally we consider the fate of the system as the
star continues to evolve beyond the main sequence, and we find that the
obliquity of the system will not undergo major variations as the star climbs
the red giant branch. We follow the evolution of the system and find that the
innermost planet will be engulfed in ~129 Myr. Furthermore we put an upper
limit of ~155 Myr for the engulfment of the second planet. This corresponds to
~ 3% of the current age of the star.
Nutzer