[en] We report on the discovery of a transiting Earth-sized (0.95R[SUB]⊕[/SUB]) planet around an M3.5 dwarf star at 57 pc, EPIC 249631677. The planet has a period of ∼3.14 days, i.e., ∼π, with an installation of 7.45 S[SUB]⊕[/SUB]. The detection was made using publicly available data from K2's Campaign 15. We observed three additional transits with SPECULOOS Southern and Northern Observatories, and a stellar spectrum from Keck/HIRES, which allowed us to validate the planetary nature of the signal. The confirmed planet is well suited for comparative terrestrial exoplanetology. While exoplanets transiting ultracool dwarfs present the best opportunity for atmospheric studies of terrestrial exoplanets with the James Webb Space Telescope, those orbiting mid-M dwarfs within 100 pc such as EPIC 249631677b will become increasingly accessible with the next generation of observatories.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Niraula, Prajwal; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
de Wit, Julien; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
Rackham, Benjamin V.; 51 Pegasi b Fellow.
Ducrot, Elsa ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Exotic
Burdanov, Artem; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
Crossfield, Ian J. M.; Kansas University, Department of Physics and Astronomy, 1082 Malott, 1251 Wescoe Hall Drive, Lawrence, KS 66045, USA
Van Grootel, Valérie ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
