Precise mass and radius of a transiting super-Earth planet orbiting the M dwarf TOI-1235: a planet in the radius gap?
Journal article, 2020

We report the confirmation of a transiting planet around the bright weakly active M0.5 V star TOI-1235 (TYC 4384-1735-1, V ≈ 11.5 mag), whose transit signal was detected in the photometric time series of sectors 14, 20, and 21 of the TESS space mission. We confirm the planetary nature of the transit signal, which has a period of 3.44 d, by using precise RV measurements with the CARMENES, HARPS-N, and iSHELL spectrographs, supplemented by high-resolution imaging and ground-based photometry. A comparison of the properties derived for TOI-1235 b with theoretical models reveals that the planet has a rocky composition, with a bulk density slightly higher than that of Earth. In particular, we measure a mass of Mp = 5.9 ± 0.6 M⊕ and a radius of Rp = 1.69 ± 0.08 R⊕, which together result in a density of ρp = 6.7- 1.1+ 1.3 g cm-3. When compared with other well-characterized exoplanetary systems, the particular combination of planetary radius and mass places our discovery in the radius gap, which is a transition region between rocky planets and planets with significant atmospheric envelopes. A few examples of planets occupying the radius gap are known to date. While the exact location of the radius gap for M dwarfs is still a matter of debate, our results constrain it to be located at around 1.7 R⊕ or larger at the insolation levels received by TOI-1235 b (~60 S⊕). This makes it an extremely interesting object for further studies of planet formation and atmospheric evolution.

techniques: photometric

stars: individual: TOI-1235

techniques: radial velocities

Astrophysics - Solar and Stellar Astrophysics

Astrophysics - Earth and Planetary Astrophysics

stars: late-type

Author

P. Bluhm

Heidelberg University

R. Luque

Instituto de Astrofísica de Canarias

University of La Laguna

N. Espinoza

Space Telescope Science Institute (STScI)

E. Palle

Instituto de Astrofísica de Canarias

University of La Laguna

J. A. Caballero

Spanish National Research Council (CSIC)

S. Dreizler

University of Göttingen

J. Livingston

University of Tokyo

S. Mathur

Instituto de Astrofísica de Canarias

University of La Laguna

A. Quirrenbach

Heidelberg University

S. Stock

Heidelberg University

V. Van Eylen

University College London (UCL)

G. Nowak

University of La Laguna

Instituto de Astrofísica de Canarias

E. D. Lopez

National Aeronautics and Space Administration (NASA)

Szilard Csizmadia

German Aerospace Center (DLR)

M. Zapatero-Osorio

Spanish National Research Council (CSIC)

P. Schöfer

University of Göttingen

J. Lillo-Box

Spanish National Research Council (CSIC)

M. Oshagh

Instituto de Astrofísica de Canarias

University of La Laguna

E. González-Álvarez

Spanish National Research Council (CSIC)

P. J. Amado

Spanish National Research Council (CSIC)

D. Barrado

Spanish National Research Council (CSIC)

V. J. S. Bejar

Instituto de Astrofísica de Canarias

University of La Laguna

B. Cale

National Aeronautics and Space Administration (NASA)

P. Chaturvedi

Thüringer Landessternwarte Tautenburg

C. Cifuentes

Spanish National Research Council (CSIC)

W. D. Cochran

The University of Texas at Austin

K. I. Collins

George Mason University

M. Cortés-Contreras

Spanish National Research Council (CSIC)

E. Díez Alonso

University of Oviedo

M. El Mufti

University of Khartoum

George Mason University

A. Ercolino

Campo Catino Astronomical Observatory

Malcolm Fridlund

Leiden University

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

E. Gaidos

University of Hawaii

R. A. Garcia

University Paris-Saclay

Iskra Georgieva

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

L. Gonzalez-Cuesta

Instituto de Astrofísica de Canarias

University of La Laguna

P. Guerra

Albanyà Astronomical Observatory

Artie P. Hatzes

Thüringer Landessternwarte Tautenburg

Th Henning

Max Planck Society

E. Herrero

Spanish National Research Council (CSIC)

D. Hidalgo

Instituto de Astrofísica de Canarias

University of La Laguna

G. Isopi

Campo Catino Astronomical Observatory

S. V. Jeffers

University of Göttingen

J. M. Jenkins

National Aeronautics and Space Administration (NASA)

E. L. N. Jensen

Swarthmore College

P. Kabath

Czech Academy of Sciences

A. Kaminski

Heidelberg University

J. Kemmer

Heidelberg University

Judith Korth

University of Cologne

D. Kossakowski

Max Planck Society

M. Kürster

Max Planck Society

M. Lafarga

Spanish National Research Council (CSIC)

F. Mallia

Campo Catino Astronomical Observatory

D. Montes

Complutense University

J. C. Morales

Spanish National Research Council (CSIC)

M. Morales-Calderon

Spanish National Research Council (CSIC)

F. Murgas

University of La Laguna

Instituto de Astrofísica de Canarias

N. Narita

Instituto de Astrofísica de Canarias

University of Tokyo

V. M. Passegger

University of Hamburg

University of Oklahoma

S. Pedraz

CAHA- Centro Astronómico Hispano-Alemán

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

P. Plavchan

George Mason University

H. Rauer

German Aerospace Center (DLR)

Technische Universität Berlin

S. Redfield

Wesleyan University

S. Reffert

Heidelberg University

A. Reiners

University of Göttingen

I Ribas

Spanish National Research Council (CSIC)

G. Ricker

Massachusetts Institute of Technology (MIT)

C. Rodíguez-López

Spanish National Research Council (CSIC)

A. R. G. Santos

Space Science Institute

S. Seager

Massachusetts Institute of Technology (MIT)

M. Schlecker

Max Planck Society

A. Schweitzer

University of Hamburg

Y. Shan

University of Göttingen

M. G. Soto

Queen Mary University of London

J. Subjak

Czech Academy of Sciences

L. Tal-Or

Ariel University

University of Göttingen

T. Trifonov

Max Planck Society

S. Vanaverbeke

KU Leuven

AstroLAB IRIS

R. Vanderspek

Massachusetts Institute of Technology (MIT)

J. Wittrock

George Mason University

M. Zechmeister

University of Göttingen

F. Zohrabi

Mississippi State University

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 639 A132

Exoplanets from space – CHEOPS and PLATO, ESA’s next two projects

Swedish National Space Board (174/18), 2017-01-01 -- 2022-12-31.

Subject Categories (SSIF 2011)

Astronomy, Astrophysics and Cosmology

Roots

Basic sciences

DOI

10.1051/0004-6361/202038160

More information

Latest update

3/16/2025