On the dynamical habitability of Trojan planets in exoplanetary systems

Author(s)
Richard Schwarz, Barbara Funk, Akos Bazso, Siegfried Eggl
Abstract

Besides the hierarchical configurations exoplanets have been observed in so far, Earth-analogs can theoretically exist in co-orbital motion with giant planets. Those so-called Trojan planets share the same orbit as their Jovian hosts, trailing or leading by approximately 60 degrees in mean anomaly. If a giant planet was situated in the habitable zone (HZ) of an exoplanetary system coorbital terrestrial worlds could in principle also be habitable provided their orbits are "tame enough". In this paper, we study the dynamical properties of Earth-like Trojan planets in their host stars' respective HZs. We investigate the orbital stability of possible Trojan planets near the Lagrangian equilibrium points L_4 and L_5 for several candidate systems. Our numerical simulations have been carried out using the planar three-body problem, in case the extrasolar system contains only one known planet and the n-body problem with more than one planet in the system. We study the stability region around the equilibrium points and counted the number of stable orbits concentrating on the dependencies between the semimajor axis, the eccentricity and the argument of perihelion of the Trojan planet. We found that of the investigated 14 systems 6 support stable Trojan planets in the system's HZ, namely HD 5891, HD 28185, WASP-41, HD 11755, HD 221287 and HD 13908.

Organisation(s)
Department of Astrophysics
Pages
155-179
Publication date
03-2017
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Portal url
https://ucrisportal.univie.ac.at/en/publications/5139dc39-6c8b-49a1-ade2-11fcb4d710a6