The Host Stars of Keplers Habitable Exoplanets: Superflares, Rotation and Activity

Abstract

We embark on a detailed study of the lightcurves of Keplers most Earth-like exoplanet host stars using the full length of Kepler data. We derive rotation periods, photometric activity indices, flaring energies, mass loss rates, gyrochronological ages, X-ray luminosities and consider implications for the planetary magnetospheres and habitability. Furthermore, we present the detection of superflares in the lightcurve of Kepler-438, the exoplanet with the highest Earth Similarity Index to date. Kepler-438b orbits at a distance of 0.166AU to its host star, and hence may be susceptible to atmospheric stripping. Our sample is taken from the Habitable Exoplanet Catalogue, and consists of the stars Kepler-22, Kepler-61, Kepler-62, Kepler-174, Kepler-186, Kepler-283, Kepler-296, Kepler-298, Kepler-438, Kepler-440, Kepler-442, Kepler-443 and KOI-4427, between them hosting 15 of the most habitable transiting planets known to date from Kepler.

Accepted by MNRAS, 18 pages, 16 figures

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Cited by in corpus (13)

• The Kepler Catalog of Stellar Flares
• MOST Observations of our Nearest Neighbor: Flares on Proxima Centauri
• Statistical Properties of Quasi-Periodic Pulsations in White-Light Flares Observed With Kepler
• K2 Ultracool Dwarfs Survey. III. White Light Flares are Ubiquitous in M6-L0 Dwarfs
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• Observation of a possible superflare on Proxima Centauri
• Polarization Criterion in Targeted SETI Observation
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• A Readily Implemented Atmosphere Sustainability Constraint for Terrestrial Exoplanets Orbiting Magnetically Active Stars
• New models of reflection spectra for terrestrial exoplanets: Present and prebiotic Earth orbiting around stars of different spectral types