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

Instituto de Astrofísica de Canarias

University of Tokyo

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

National Institutes of Natural Sciences

The Graduate University for Advanced Studies (SOKENDAI)

F. Murgas

University of La Laguna

Instituto de Astrofísica de Canarias

Norio Narita

National Institutes of Natural Sciences

University of Tokyo

Instituto de Astrofísica de Canarias

Masashi Omiya

National Institutes of Natural Sciences

Jaume Orell-Miquel

University of La Laguna

Instituto de Astrofísica de Canarias

Enric Palle

University of La Laguna

Instituto de Astrofísica de Canarias

Quentin Changeat

European Space Agcy ESA, Space Telescope Sci Inst STScI, ESA Off

University College London (UCL)

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

Spanish National Research Council (CSIC)

Institute of Space Studies of Catalonia (IEEC)

Mayuko Mori

University of Tokyo

Evangelos Nagel

University of Göttingen

Hannu Parviainen

University of La Laguna

Instituto de Astrofísica de Canarias

Volker Perdelwitz

Ariel University

Ansgar Reiners

University of Göttingen

Ignasi Ribas

Institute of Space Studies of Catalonia (IEEC)

Jorge Sanz-Forcada

Spanish Astrobiology Center (INTA-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

Instituto de Astrofísica de Canarias

University of La Laguna

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

Instituto de Astrofísica de Canarias

University of La Laguna

Ilaria Carleo

University of La Laguna

David Charbonneau

Harvard-Smithsonian Center for Astrophysics

Karen A. Collins

Harvard-Smithsonian Center for Astrophysics

Thayne Currie

National Astronomical Observatory of Japan

University of Texas at San Antonio

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

Instituto de Astrofísica de Canarias

University of La Laguna

Samuel Geraldia-Gonzalez

University of La Laguna

Instituto de Astrofísica de Canarias

Josafat Gonzalez-Rodriguez

University of La Laguna

Instituto de Astrofísica de Canarias

Christina Hedges

University of Maryland, Baltimore

NASA Goddard Space Flight Center

Thomas Henning

Max Planck Institute for Astronomy

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

NASA Ames Research Center

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

National Institutes of Natural Sciences

Tokyo University of Agriculture and Technology

M. Stangret

Istituto nazionale di astrofisica (INAF)

Aoi Takahashi

National Institutes of Natural Sciences

Huan-Yu Teng

Chinese Academy of Sciences

Tokyo Institute of Technology

Motohide Tamura

University of Tokyo

National Institutes of Natural Sciences

Yuka Terada

Academia Sinica

National Taiwan University

Akitoshi Ueda

The Graduate University for Advanced Studies (SOKENDAI)

National Institutes of Natural Sciences

Tomonori Usuda

National Institutes of Natural Sciences

The Graduate University for Advanced Studies (SOKENDAI)

Sebastien Vievard

National Institutes of Natural Sciences

National Astronomical Observatory of Japan

David Watanabe

Planetary Discoveries

Joshua N. Winn

Princeton University

Astrophysical Journal Letters

2041-8205 (ISSN) 2041-8213 (eISSN)

Vol. 969 1 L21

Subject Categories

Astronomy, Astrophysics and Cosmology

DOI

10.3847/2041-8213/ad3642

More information

Latest update

8/19/2024