2014/07/03 by Paul Robertson, Suvrath Mahadevan, Michael Endl +1
Physics and Astronomy · #Astro and Planetary Science #Astrobiology #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Circumstellar habitable zone #Exoplanet #Physics #Planet #Planetary system #Stars #Stellar rotation #Stellar, planetary, and galactic studies #Super-Earth #Terrestrial planet #astro-ph.EP
paper · pdf · doi:10.1126/science.1253253
This is the author's version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in Science Express (3 July 2014), doi:10.1126/science.1253253
arxiv created 2014/07/03 · openalex publication_date 2014/07/04 · arxiv updated 2014/07/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The M dwarf star Gliese 581 is believed to host four planets, including one (GJ 581d) near the habitable zone that could possibly support liquid water on its surface if it is a rocky planet. The detection of another habitable-zone planet--GJ 581g--is disputed, as its significance depends on the eccentricity assumed for d. Analyzing stellar activity using the Hα line, we measure a stellar rotation period of 130 ± 2 days and a correlation for Hα modulation with radial velocity. Correcting for activity greatly diminishes the signal of GJ 581d (to 1.5 standard deviations) while significantly boosting the signals of the other known super-Earth planets. GJ 581d does not exist, but is an artifact of stellar activity which, when incompletely corrected, causes the false detection of planet g.