Spin evolution of Earth-sized exoplanets, including atmospheric tides and core-mantle friction

Abstract

Planets with masses between 0.1 - 10 M_earth are believed to host dense atmospheres. These atmospheres can play an important role on the planet's spin evolution, since thermal atmospheric tides, driven by the host star, may counterbalance gravitational tides. In this work we study the long-term spin evolution of Earth-sized exoplanets. We generalize previous works by including the effect of eccentric orbits and obliquity. We show that under the effect of tides and core-mantle friction, the obliquity of the planets evolve either to 0 or 180 degrees. The rotation of these planets is also expected to evolve into a very restricted number of equilibrium configurations. In general, none of this equilibria is synchronous with the orbital mean motion. The role of thermal atmospheric tides becomes more important for Earth-sized planets in the habitable zones of their systems, so they cannot be neglected when we search for their potential habitability.

25 pages, 11 figures, 2 tables, International Journal of Astrobiology, 2014

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Cited by in corpus (9)

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• Why do warm Neptunes present nonzero eccentricity?
• Complete spin and orbital evolution of close-in bodies using a Maxwell viscoelastic rheology
• Milankovitch Cycles of Terrestrial Planets in Binary Star Systems
• A Helicity-Based Method to Infer the CME Magnetic Field Magnitude in Sun and Geospace: Generalization and Extension to Sun-Like and M-Dwarf Stars and Implications for Exoplanet Habitability
• Spin dynamics of close-in planets exhibiting large TTVs
• Consequences of dynamically unstable moons in extrasolar systems
• Tidal evolution of Earth-like planets in the habitable zone of low-mass stars
• The Feasibility of Asynchronous Rotation via Thermal Tides for Diverse Atmospheric Compositions