The Astronomical Journal (Jan 2023)
An Earth-sized Planet around an M5 Dwarf Star at 22 pc
- Teruyuki Hirano,
- Fei Dai,
- John H. Livingston,
- Sascha Grziwa,
- Kristine W. F. Lam,
- Yui Kasagi,
- Norio Narita,
- Hiroyuki Tako Ishikawa,
- Kohei Miyakawa,
- Luisa M. Serrano,
- Yuji Matsumoto,
- Eiichiro Kokubo,
- Tadahiro Kimura,
- Masahiro Ikoma,
- Joshua N. Winn,
- John P. Wisniewski,
- Hiroki Harakawa,
- Huan-Yu Teng,
- William D. Cochran,
- Akihiko Fukui,
- Davide Gandolfi,
- Eike W. Guenther,
- Yasunori Hori,
- Kai Ikuta,
- Kiyoe Kawauchi,
- Emil Knudstrup,
- Judith Korth,
- Takayuki Kotani,
- Vigneshwaran Krishnamurthy,
- Tomoyuki Kudo,
- Takashi Kurokawa,
- Masayuki Kuzuhara,
- Rafael Luque,
- Mayuko Mori,
- Jun Nishikawa,
- Masashi Omiya,
- Jaume Orell-Miquel,
- Enric Palle,
- Carina M. Persson,
- Seth Redfield,
- Eugene Serabyn,
- Alexis M. S. Smith,
- Aoi Takahashi,
- Takuya Takarada,
- Akitoshi Ueda,
- Vincent Van Eylen,
- Sébastien Vievard,
- Motohide Tamura,
- Bun’ei Sato
Affiliations
- Teruyuki Hirano
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI) , 2-21-1, Osawa, Mitaka, Tokyo, 181–8588, Japan
- Fei Dai
- ORCiD
- Division of Geological and Planetary Sciences , 1200 E California Boulevard, Pasadena, CA 91125, USA; Department of Astronomy, California Institute of Technology , Pasadena, CA 91125, USA; NASA Sagan Fellow
- John H. Livingston
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI) , 2-21-1, Osawa, Mitaka, Tokyo, 181–8588, Japan
- Sascha Grziwa
- ORCiD
- Rheinisches Institut fuer Umweltforschung an der Universitaet zu Koeln , Aachener Strasse 209, D-50931 Koeln, Germany
- Kristine W. F. Lam
- Institute of Planetary Research , German Aerospace Center (DLR), Rutherfordstrasse 2, D-12489 Berlin, Germany
- Yui Kasagi
- ORCiD
- National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI) , 2-21-1, Osawa, Mitaka, Tokyo, 181–8588, Japan
- Norio Narita
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; Komaba Institute for Science, The University of Tokyo , 3-8-1 Komaba, Meguro, Tokyo 153–8902, Japan; Instituto de Astrofísica de Canarias (IAC) , E-38205 La Laguna, Tenerife, Spain
- Hiroyuki Tako Ishikawa
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Kohei Miyakawa
- ORCiD
- National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Luisa M. Serrano
- ORCiD
- Dipartimento di Fisica, Universitá di Torino , Via P. Giuria 1, I-10125, Torino, Italy
- Yuji Matsumoto
- ORCiD
- National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Eiichiro Kokubo
- ORCiD
- National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Tadahiro Kimura
- ORCiD
- Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113–0033, Japan
- Masahiro Ikoma
- ORCiD
- National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113–0033, Japan
- Joshua N. Winn
- ORCiD
- Department of Astrophysical Sciences, Princeton University , 4 Ivy Lane, Princeton, NJ 08544, USA
- John P. Wisniewski
- ORCiD
- George Mason University Department of Physics & Astronomy , 4400 University Drive, MS 3F3, Fairfax, VA 22030, USA
- Hiroki Harakawa
- ORCiD
- Subaru Telescope , 650 N. Aohoku Place, Hilo, HI 96720, USA
- Huan-Yu Teng
- ORCiD
- Department of Earth and Planetary Sciences, Tokyo Institute of Technology , Meguro-ku, Tokyo, 152–8551, Japan
- William D. Cochran
- ORCiD
- Center for Planetary Systems Habitability and McDonald Observatory, The University of Texas , Austin Texas 78730, USA
- Akihiko Fukui
- ORCiD
- Komaba Institute for Science, The University of Tokyo , 3-8-1 Komaba, Meguro, Tokyo 153–8902, Japan; Instituto de Astrofísica de Canarias (IAC) , E-38205 La Laguna, Tenerife, Spain
- Davide Gandolfi
- ORCiD
- Dipartimento di Fisica, Universitá di Torino , Via P. Giuria 1, I-10125, Torino, Italy
- Eike W. Guenther
- ORCiD
- Thüringer Landessternwarte Tautenburg , Sternwarte 5, D-07778 Tautenburg, Germany
- Yasunori Hori
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI) , 2-21-1, Osawa, Mitaka, Tokyo, 181–8588, Japan
- Kai Ikuta
- ORCiD
- Department of Multi-Disciplinary Sciences, Graduate School of Arts and Sciences, The University of Tokyo , 3-8-1 Komaba, Meguro, Tokyo 153–8902, Japan
- Kiyoe Kawauchi
- ORCiD
- Department of Multi-Disciplinary Sciences, Graduate School of Arts and Sciences, The University of Tokyo , 3-8-1 Komaba, Meguro, Tokyo 153–8902, Japan
- Emil Knudstrup
- ORCiD
- Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University , Ny Munkegade 120, DK-8000 Aarhus C, Denmark
- Judith Korth
- ORCiD
- Department of Space, Earth and Environment, Astronomy and Plasma Physics, Chalmers University of Technology , SE-412 96 Gothenburg, Sweden
- Takayuki Kotani
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI) , 2-21-1, Osawa, Mitaka, Tokyo, 181–8588, Japan
- Vigneshwaran Krishnamurthy
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Tomoyuki Kudo
- ORCiD
- Subaru Telescope , 650 N. Aohoku Place, Hilo, HI 96720, USA
- Takashi Kurokawa
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; Institute of Engineering, Tokyo University of Agriculture and Technology , 2-24-16, Nakacho, Koganei, Tokyo, 184–8588, Japan
- Masayuki Kuzuhara
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Rafael Luque
- ORCiD
- Department of Astronomy & Astrophysics, University of Chicago , Chicago, IL 60637, USA
- Mayuko Mori
- ORCiD
- Department of Astronomy, Graduate School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Jun Nishikawa
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomical Science, School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI) , 2-21-1, Osawa, Mitaka, Tokyo, 181–8588, Japan
- Masashi Omiya
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Jaume Orell-Miquel
- ORCiD
- Instituto de Astrofísica de Canarias (IAC) , E-38205 La Laguna, Tenerife, Spain; Departamento de Astrofísica, Universidad de La Laguna (ULL) , E-38206 La Laguna, Tenerife, Spain
- Enric Palle
- ORCiD
- Instituto de Astrofísica de Canarias (IAC) , E-38205 La Laguna, Tenerife, Spain; Departamento de Astrofísica, Universidad de La Laguna (ULL) , E-38206 La Laguna, Tenerife, Spain
- Carina M. Persson
- ORCiD
- Department of Space, Earth and Environment, Chalmers University of Technology , Onsala Space Observatory, SE-439 92 Onsala, Sweden
- Seth Redfield
- ORCiD
- Astronomy Department and Van Vleck Observatory, Wesleyan University , Middletown, CT 06459, USA
- Eugene Serabyn
- Jet Propulsion Laboratory, California Institute of Technology , Pasadena, CA 91109, USA
- Alexis M. S. Smith
- ORCiD
- Institute of Planetary Research , German Aerospace Center, Rutherfordstrasse 2, D-12489 Berlin, Germany
- Aoi Takahashi
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Takuya Takarada
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Akitoshi Ueda
- National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan
- Vincent Van Eylen
- ORCiD
- Mullard Space Science Laboratory, University College London , Holmbury St Mary, Dorking, Surrey RH5 6NT, UK
- Sébastien Vievard
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; Subaru Telescope , 650 N. Aohoku Place, Hilo, HI 96720, USA
- Motohide Tamura
- ORCiD
- Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan ; [email protected]; National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181–8588, Japan; Department of Astronomy, Graduate School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Bun’ei Sato
- ORCiD
- Department of Earth and Planetary Sciences, Tokyo Institute of Technology , Meguro-ku, Tokyo, 152–8551, Japan
- DOI
- https://doi.org/10.3847/1538-3881/acb7e1
- Journal volume & issue
-
Vol. 165,
no. 3
p. 131
Abstract
We report on the discovery of an Earth-sized transiting planet ( R _p = 1.015 ± 0.051 R _⊕ ) in a P = 4.02 day orbit around K2-415 (EPIC 211414619), an M5V star at 22 pc. The planet candidate was first identified by analyzing the light-curve data obtained by the K2 mission, and it is here shown to exist in the most recent data from TESS. Combining the light curves with the data secured by our follow-up observations, including high-resolution imaging and near-infrared spectroscopy with IRD, we rule out false-positive scenarios, finding a low false-positive probability of 2 × 10 ^−4 . Based on IRD’s radial velocities of K2-415, which were sparsely taken over three years, we obtain a planet mass of 3.0 ± 2.7 M _⊕ ( M _p < 7.5 M _⊕ at 95% confidence) for K2-415b. Being one of the lowest-mass stars (≈0.16 M _⊙ ) known to host an Earth-sized transiting planet, K2-415 will be an interesting target for further follow-up observations, including additional radial velocity monitoring and transit spectroscopy.
Keywords
- Transit photometry
- High angular resolution
- High-resolution spectroscopy
- Exoplanet formation
- Radial velocity
