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arXiv · 2103.15902

Spin Dynamics of Extrasolar Giant Planets in Planet-Planet Scattering

Yu-Cian Hong·Dong Lai·Jonathan I. Lunine·Philip D. Nicholson
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Abstract

Planet-planet scattering best explains the eccentricity distribution of extrasolar giant planets. Past literature showed that the orbits of planets evolve due to planet-planet scattering. This work studies the spin evolution of planets in planet-planet scattering in 2-planet systems. Spin can evolve dramatically due to spin-orbit coupling made possible by the evolving spin and orbital precession during the planet-planet scattering phase. The main source of torque to planet spin is the stellar torque, and the total planet-plane torque contribution is negligible. As a consequence of the evolution of the spin, planets can end up with significant obliquity (the angle between a planet's own orbit normal and spin axis) like planets in our Solar System.

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Yu-Cian Hong, Dong Lai, Jonathan I. Lunine, Philip D. Nicholson. 2021-03-29. Spin Dynamics of Extrasolar Giant Planets in Planet-Planet Scattering. https://doi.org/10.3847/1538-4357/ac1a14

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