2009/06/15 by M. Mayor, X. Bonfils, X. Bonfıls +12 · 5 citations
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph.EP
paper · pdf · doi:10.1051/0004-6361/200912172
9 pages, A&A Accepted
arxiv created 2009/06/15 · openalex publication_date 2009/09/24 · arxiv updated 2015/05/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
The GJ 581 planetary system is already known to harbour three planets, including two super-Earth planets that straddle its habitable zone. We report the detection of an additional planet – GJ 581e – with a minimum mass of 1.9 . With a period of 3.15 days, it is the innermost planet of the system and has a ~5% transit probability. We also correct our previous confusion about the orbital period of GJ 581d (the outermost planet) with a one-year alias, benefitting from an extended time span and many more measurements. The revised period is 66.8 days, and positions the semi-major axis inside the habitable zone of the low mass star. The dynamical stability of the 4-planet system imposes an upper bound on the orbital plane inclination. The planets cannot be more massive than approximately 1.6 times their minimum mass.