[en] One focus of modern astronomy is to detect temperate terrestrial exoplanets well-suited
for atmospheric characterisation. A milestone was recently achieved with the detection
of three Earth-sized planets transiting (i.e. passing in front of) a star just 8% the mass of
the Sun 12 parsecs away. Indeed, the transiting configuration of these planets combined
with the Jupiter-like size of their host star - named TRAPPIST-1 - makes possible indepth
studies of their atmospheric properties with current and future astronomical
facilities. Here we report the results of an intensive photometric monitoring
campaign of that star from the ground and with the Spitzer Space Telescope. Our
observations reveal that at least seven planets with sizes and masses similar to the Earth
revolve around TRAPPIST-1. The six inner planets form a near-resonant chain such
that their orbital periods (1.51, 2.42, 4.04, 6.06, 9.21, 12.35 days) are near ratios of small
integers. This architecture suggests that the planets formed farther from the star and
migrated inward. The seven planets have equilibrium temperatures low enough to
make possible liquid water on their surfaces.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Gillon, Michaël ; Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa)
Triaud, Amaury; 2Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK
Demory, Brice-Olivier; University of Bern, Center for Space and Habitability, Sidlerstrasse 5, CH-3012, Bern, Switzerland
Jehin, Emmanuel ; Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa)
Agol, Eric; Astronomy Department, University of Washington, Seattle, WA, 98195, USA
Deck, Katherine; Department of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
Lederer, Susan; NASA Johnson Space Center, 2101 NASA Parkway, Houston, Texas, 77058, USA
de Wit, Julien; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts
Burdanov, Artem ; Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Origines Cosmologiques et Astrophysiques (OrCa)
Ingalls, James; Spitzer Science Center, California Institute of Technology, 1200 E California Boulevard, Mail Code 314-6, Pasadena, CA
Bolmont, Emeline; NaXys, Department of Mathematics, University of Namur, 8 Rempart de la Vierge, 5000 Namur, Belgium
Silva Fernandes, Catarina ; Space sciences, Technologies and Astrophysics Research (STAR) Institute, Université de Liège, Allée du 6 Août 17, Bat.
Holdsworth, Daniel; Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK
Kotze, Enrico; South African Astronomical Observatory, PO Box 9, Observatory 7935, Cape Town, South Africa
Van Grootel, Valérie ; Université de Liège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
Almleaky, Yaseen; Space and Astronomy Department, Faculty of Science, King Abdulaziz University, 21589 Jeddah, Saudi Arabia.
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