Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy
Journal article, 2024
Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the atmospheres of terrestrial planets via follow-up spectroscopic observations. However, the number of such planets receiving low insolation is still small, limiting our ability to understand the diversity of the atmospheric composition and climates of temperate terrestrial planets. We report the discovery of an Earth-sized planet transiting the nearby (12 pc) inactive M3.0 dwarf Gliese 12 (TOI-6251) with an orbital period (P(or)b) of 12.76 days. The planet, Gliese 12 b, was initially identified as a candidate with an ambiguous P-orb from TESS data. We confirmed the transit signal and P-orb using ground-based photometry with MuSCAT2 and MuSCAT3, and validated the planetary nature of the signal using high-resolution images from Gemini/NIRI and Keck/NIRC2 as well as radial velocity (RV) measurements from the InfraRed Doppler instrument on the Subaru 8.2 m telescope and from CARMENES on the CAHA 3.5 m telescope. X-ray observations with XMM-Newton showed the host star is inactive, with an X-ray-to-bolometric luminosity ratio of log L-X/L-bol approximate to - 5.7. Joint analysis of the light curves and RV measurements revealed that Gliese 12 b has a radius of 0.96 +/- 0.05 R-circle plus, a 3 sigma mass upper limit of 3.9M(circle plus), and an equilibrium temperature of 315 +/- 6 K assuming zero albedo. The transmission spectroscopy metric (TSM) value of Gliese 12 b is close to the TSM values of the TRAPPIST-1 planets, adding Gliese 12 b to the small list of potentially terrestrial, temperate planets amenable to atmospheric characterization with JWST.
Author
Masayuki Kuzuhara
National Institutes of Natural Sciences
A. Fukui
University of Tokyo
Instituto de Astrofísica de Canarias
J.H. Livingston
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
Jerome P. De Leon
University of Tokyo
Teruyuki Hirano
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Yui Kasagi
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
F. Murgas
University of La Laguna
Instituto de Astrofísica de Canarias
Norio Narita
University of Tokyo
Instituto de Astrofísica de Canarias
National Institutes of Natural Sciences
Masashi Omiya
National Institutes of Natural Sciences
Jaume Orell-Miquel
Instituto de Astrofísica de Canarias
University of La Laguna
Enric Palle
University of La Laguna
Instituto de Astrofísica de Canarias
Quentin Changeat
University College London (UCL)
European Space Agcy ESA, Space Telescope Sci Inst STScI, ESA Off
Emma Esparza-Borges
Instituto de Astrofísica de Canarias
University of La Laguna
Hiroki Harakawa
National Astronomical Observatory of Japan
Coel Hellier
Keele University
Yasunori Hori
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Hiroyuki Tako Ishikawa
Western University
Takanori Kodama
Tokyo Institute of Technology
Takayuki Kotani
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Tomoyuki Kudo
National Astronomical Observatory of Japan
Juan C. Morales
Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
Spanish National Research Council (CSIC)
Mayuko Mori
University of Tokyo
Evangelos Nagel
University of Göttingen
Hannu Parviainen
Instituto de Astrofísica de Canarias
University of La Laguna
Volker Perdelwitz
Ariel University
Ansgar Reiners
University of Göttingen
Ignasi Ribas
Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
Jorge Sanz-Forcada
Spanish National Research Council (CSIC)
Bun'ei Sato
Tokyo Institute of Technology
Andreas Schweitzer
Hamburg Observatory
Hugo M. Tabernero
Complutense University
Takuya Takarada
National Institutes of Natural Sciences
Taichi Uyama
The California State University
Mathias Zechmeister
University of Göttingen
Nestor Abreu Garcia
University of La Laguna
Instituto de Astrofísica de Canarias
Charles Beichman
California Institute of Technology (Caltech)
Victor J. S. Bejar
University of La Laguna
Timothy D. Brandt
University of California at Santa Barbara
Yessica Calatayud-Borras
University of La Laguna
Instituto de Astrofísica de Canarias
Ilaria Carleo
University of La Laguna
David Charbonneau
Harvard-Smithsonian Center for Astrophysics
Karen A. Collins
Harvard-Smithsonian Center for Astrophysics
Thayne Currie
University of Texas at San Antonio
National Astronomical Observatory of Japan
John P. Doty
Noqsi Aerospace Ltd
Stefan Dreizler
University of Göttingen
Gareb Fernandez-Rodriguez
University of La Laguna
Instituto de Astrofísica de Canarias
Izuru Fukuda
University of Tokyo
Daniel Galan
University of La Laguna
Instituto de Astrofísica de Canarias
Samuel Geraldia-Gonzalez
University of La Laguna
Instituto de Astrofísica de Canarias
Josafat Gonzalez-Rodriguez
Instituto de Astrofísica de Canarias
University of La Laguna
Christina Hedges
University of Maryland, Baltimore
National Aeronautics and Space Administration (NASA)
Thomas Henning
Max Planck Society
Klaus Hodapp
University of Hawaii
Masahiro Ikoma
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
Keisuke Isogai
Kyoto University
Shane Jacobson
University of Hawaii
Markus Janson
Stockholm University
Jon M. Jenkins
National Aeronautics and Space Administration (NASA)
Taiki Kagetani
University of Tokyo
Yugo Kawai
University of Tokyo
Kiyoe Kawauchi
Ritsumeikan University
Eiichiro Kokubo
National Institutes of Natural Sciences
Mihoko Konishi
Oita University
Judith Korth
Lund University
Vigneshwaran Krishnamurthy
McGill University
Université de Montréal
Takashi Kurokawa
National Institutes of Natural Sciences
Tokyo University of Agriculture and Technology
Nobuhiko Kusakabe
National Institutes of Natural Sciences
Jungmi Kwon
University of Tokyo
Andres Laza-Ramos
Universitat de Valencia
Florence Libotte Rafael Luque
University of La Laguna
Alberto Madrigal-Aguado
University of Chicago
Yuji Matsumoto
National Institutes of Natural Sciences
Dimitri Mawet
California Institute of Technology (Caltech)
Pedro Pablo Meni Gallardo
University of La Laguna
Giuseppe Morello
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Sara Munoz Torres
University of La Laguna
Jun Nishikawa
National Institutes of Natural Sciences
Stevanus K. Nugroho
National Institutes of Natural Sciences
Masahiro Ogihara
Shanghai Jiao Tong University
Alberto Pelaez-Torres
University of La Laguna
David Rapetti
Universities Space Research Association
M. Sánchez-Benavente
University of La Laguna
Martin Schlecker
University of Arizona
Sara Seager
Massachusetts Institute of Technology (MIT)
Takuma Serizawa
Tokyo University of Agriculture and Technology
National Institutes of Natural Sciences
M. Stangret
Istituto nazionale di astrofisica (INAF)
Aoi Takahashi
National Institutes of Natural Sciences
Huan-Yu Teng
Tokyo Institute of Technology
Chinese Academy of Sciences
Motohide Tamura
University of Tokyo
National Institutes of Natural Sciences
Yuka Terada
National Taiwan University
Academia Sinica
Akitoshi Ueda
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
Tomonori Usuda
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
Sebastien Vievard
National Astronomical Observatory of Japan
National Institutes of Natural Sciences
David Watanabe
Planetary Discoveries
Joshua N. Winn
Princeton University
Astrophysical Journal Letters
2041-8205 (ISSN) 2041-8213 (eISSN)
Vol. 969 1 L21Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
DOI
10.3847/2041-8213/ad3642