2008/08/01 by Alexandre C. M. Correia, A. C. M. Correia, B. Levrard +3 · 1 citation
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Astro and Planetary Science #Geomagnetism and Paleomagnetism Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:200810388
4 pages, 2 figures. accepted for publication in Astronomy and Astrophysics. to be published in Astronomy and Astrophysics
openalex publication_date 2008/08/01 · arxiv created 2008/08/07 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
The equilibrium rotation of tidally evolved “Earth-like” extra-solar planets is often assumed to be synchronous with their orbital mean motion. The same assumption persisted for Mercury and Venus until radar observations revealed their true spin rates. As many of these planets follow eccentric orbits and are believed to host dense atmospheres, we expect the equilibrium rotation to differ from the synchronous motion. Here we provide a general description of the allowed final equilibrium rotation states of these planets, and apply this to already discovered cases in which the mass is lower than 12 . At low obliquity and moderate eccentricity, it is shown that there are at most four distinct equilibrium possibilities, one of which can be retrograde. Because most presently known “Earth-like” planets present eccentric orbits, their equilibrium rotation is unlikely to be synchronous.