GJ 367b: A dense, ultrashort-period sub-Earth planet transiting a nearby red dwarf star
Journal article, 2021

Ultrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 ± 0.054 Earth-radii and a mass of 0.546 ± 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8.106 ± 2.165 grams per cubic centimeter—close to that of iron. An interior structure model predicts that the planet has an iron core radius fraction of 86 ± 5%, similar to that of Mercury’s interior.

Author

K. W.F. Lam

German Aerospace Center (DLR)

Technische Universität Berlin

Szilárd Csizmadia

German Aerospace Center (DLR)

N. Astudillo-Defru

Universidad Catolica de la Santisima Concepcion

X. Bonfils

Grenoble Alpes University

D. Gandolfi

University of Turin

Sebastiano Padovan

German Aerospace Center (DLR)

European Organisation for the Exploitation of Meteorological Satellites

M. Esposito

Thüringer Landessternwarte Tautenburg

Coel Hellier

Keele University

T. Hirano

National Institutes of Natural Sciences

Tokyo Institute of Technology

J.H. Livingston

University of Tokyo

F. Murgas

University of La Laguna

Instituto de Astrofísica de Canarias

Alexis M. S. Smith

German Aerospace Center (DLR)

Karen A. Collins

Harvard-Smithsonian Center for Astrophysics

S. Mathur

University of La Laguna

Instituto de Astrofísica de Canarias

R. A. García

The French Alternative Energies and Atomic Energy Commission (CEA)

University Paris-Saclay

S.B. Howell

NASA Ames Research Center

N. C. Santos

University of Porto

Fei Dai

California Institute of Technology (Caltech)

George R. Ricker

Massachusetts Institute of Technology (MIT)

Roland K. Vanderspek

Massachusetts Institute of Technology (MIT)

D. W. Latham

Harvard-Smithsonian Center for Astrophysics

S. Seager

Massachusetts Institute of Technology (MIT)

J. N. Winn

Princeton University

Jon M. Jenkins

NASA Ames Research Center

Simon Albrecht

Aarhus University

J. M. Almenara

Grenoble Alpes University

E. Artigau

Grenoble Alpes University

O. Barragán

University of Oxford

F. Bouchy

University of Geneva

J. Cabrera

Grenoble Alpes University

D. Charbonneau

Harvard-Smithsonian Center for Astrophysics

Priyanka Chaturvedi

Thüringer Landessternwarte Tautenburg

Alexander Chaushev

Technische Universität Berlin

Jessie L. Christiansen

California Institute of Technology (Caltech)

William D. Cochran

The University of Texas at Austin

José R. de Meideiros

Federal University of Rio Grande do Norte

X. Delfosse

Grenoble Alpes University

R. F. Diaz

Escuela de Economía y Negocios

René Doyon

Université de Montréal

P. Eigmüller

German Aerospace Center (DLR)

P. Figueira

European Southern Observatory Santiago

University of Porto

T. Forveille

Grenoble Alpes University

Malcolm Fridlund

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Leiden University

G. Gaisné

Grenoble Alpes University

E. Goffo

Thüringer Landessternwarte Tautenburg

University of Turin

Iskra Georgieva

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Extragalactic Astrophysics

S. Grziwa

University of Cologne

E. W. Guenther

Thüringer Landessternwarte Tautenburg

A. Hatzes

Thüringer Landessternwarte Tautenburg

M.C. Johnson

Las Cumbres Observatory Global Telescope Network

Petr Kabath

Academy of Sciences of the Czech Republic v.v.i

E. Knudstrup

Aarhus University

Judith Korth

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Extragalactic Astrophysics

University of Cologne

Pablo Lewin

Maury Lewin Astronomical Observatory

Jack J. Lissauer

NASA Ames Research Center

Stanford University

C. Lovis

University of Geneva

R. Luque

University of La Laguna

Instituto de Astrofísica de Canarias

C. Melo

European Southern Observatory Santiago

Edward H. Morgan

Massachusetts Institute of Technology (MIT)

Robert Morris

NASA Ames Research Center

Search for Extraterrestrial Intelligence Institute

Michel Mayor

University of Geneva

Norio Narita

Astrobiology Center, Japan

University of Tokyo

Japan Science and Technology Agency

Instituto de Astrofísica de Canarias

H. L.M. Osborne

University College London (UCL)

Enric Palle

Instituto de Astrofísica de Canarias

University of La Laguna

Francesco Pepe

University of Geneva

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Samuel N. Quinn

Harvard-Smithsonian Center for Astrophysics

H. Rauer

Technische Universität Berlin

Freie Universität Berlin

German Aerospace Center (DLR)

S. Redfield

Wesleyan University

Joshua E. Schlieder

NASA Goddard Space Flight Center

D. Segransan

University of Geneva

L. M. Serrano

University of Turin

Jeffrey C. Smith

Search for Extraterrestrial Intelligence Institute

NASA Ames Research Center

J. Šubjak

Czech Academy of Sciences

Charles University

J. D. Twicken

Search for Extraterrestrial Intelligence Institute

NASA Ames Research Center

S. Udry

University of Geneva

Vincent Van Eylen

University College London (UCL)

Michael L. Vezie

Massachusetts Institute of Technology (MIT)

Science

0036-8075 (ISSN)

Vol. 374 6572 1271-1275

Subject Categories

Subatomic Physics

Astronomy, Astrophysics and Cosmology

Other Earth and Related Environmental Sciences

DOI

10.1126/science.aay3253

PubMed

34855492

More information

Latest update

12/15/2021