Effects of Flux Variation on the Surface Temperatures of Earth-like Circumbinary Planets
arXiv:2008.04992 · doi:10.1093/mnras/staa2980
Abstract
The Kepler Space telescope has uncovered around thirteen circumbinary planets (CBPs) that orbit a pair of stars and experience two sources of stellar flux. We characterize the top-of-atmosphere flux and surface temperature evolution in relation to the orbital short-term dynamics between the central binary star and an Earth-like CBP analog. We compare the differential evolution of an Earth-like CBP's flux and surface temperature with that of an equivalent single-star (ESS) system to uncover the degree by which the potential habitability of the planet could vary. For a Sun-like primary, we find that the flux variation over a single planetary orbit is greatest when the dynamical mass ratio is ~0.3 for a G-K spectral binary. Using a latitudinal energy balance model, we show that the ice-albedo feedback plays a substantial role in Earth-like CBP habitability due to the interplay between flux redistribution (via obliquity) and changes in the total flux (via binary gyration). We examine the differential evolution of flux and surface temperature for Earth-like analogs of the habitable zone CBPs (4 Kepler and 1 hypothetical system) and find that these analogs are typically warmer than their ESS counterparts.
12 pages, 14 figures, 5 tables; revised relative to first review at MNRAS, updated table 1 with Kopparapu et al. (2014) values
References in corpus (16)
- Habitable Zones Around Main-Sequence Stars: Dependence on Planetary Mass
- The Transiting Circumbinary Planets Kepler-34 and Kepler-35
- Was Venus the First Habitable World of our Solar System?
- Effects of Extreme Obliquity Variations on the Habitability of Exoplanets
- TOI-1338: TESS' First Transiting Circumbinary Planet
- Discovery of a Third Transiting Planet in the Kepler-47 Circumbinary System
- Uncovering Circumbinary Planetary Architectural Properties from Selection Biases
- Habitability of Earth-type Planets and Moons in the Kepler-16 System
- Orbital Stability of Circumstellar Planets in Binary Systems
- Kepler-1661 b: A Neptune-sized Kepler Transiting Circumbinary Planet around a Grazing Eclipsing Binary
- Exo-Milankovitch Cycles I: Orbits and Rotation States
- Instabilities in Multi-Planet Circumbinary Systems
- Surface Flux Patterns on Planets in Circumbinary Systems, and Potential for Photosynthesis
- Circumbinary Habitability Niches
- Habitable Zone Boundaries for Circumbinary Planets
- Could there be an undetected inner planet near the stability limit in Kepler-1647?