In the Presence of a Wrecking Ball: Orbital Stability in the HR 5183 System

Abstract

Discoveries of exoplanets using the radial velocity method are progressively reaching out to increasingly longer orbital periods as the duration of surveys continues to climb. The improving sensitivity to potential Jupiter analogs is revealing a diversity of orbital architectures that are substantially different from that found in our solar system. An excellent example of this is the recent discovery of HR 5183b; a giant planet on a highly eccentric ($e = 0.84$) $\sim$75~year orbit. The presence of such giant planet orbits are intrinsically interesting from the perspective of the dynamical history of planetary systems, and also for examining the implications of on-going dynamical stability and habitability of these systems. In this work, we examine the latter, providing results of dynamical simulations that explore the stable regions that the eccentric orbit of the HR 5183 giant planet allows to exist within the Habitable Zone of the host star. Our results show that, despite the incredible perturbing influence of the giant planet, there remain a narrow range of locations within the Habitable Zone where terrestrial planets may reside in long-term stable orbits. We discuss the effects of the giant planet on the potential habitability of a stable terrestrial planet, including the modulation of terrestrial planet eccentricities and the periodically spectacular view of the giant planet from the terrestrial planet location.