TOI-3493 b: A planet with a Neptune-like density transiting a bright G0-type star
Journal article, 2025

We report the discovery of TOI-3493 b, a sub-Neptune-sized planet on an 8.15-d orbit transiting the bright (V=9.3) G0 star HD 119355 (aka TIC 203377303) initially identified by NASA's TESS space mission. With the aim of confirming the planetary nature of the transit signal detected by TESS and determining the mass of the planet, we performed an intensive Doppler campaign with the HARPS spectrograph, collecting radial velocity measurements. We found that TOI-3493 b lies in a nearly circular orbit and has a mass of 9.0 ± 1.2 M⊕ and a radius of 3.22 ± 0.08 R⊕, implying a bulk density of 1.47-0.22+0.23 g cm-3, consistent with a composition comprising a small solid core surrounded by a thick H/He-dominated atmosphere.

Stars: solar-type

Planets and satellites: detection

Techniques: photometric

Techniques: radial velocities

Stars: individual: TOI-3493

Author

Priyanka Chaturvedi

Thüringer Landessternwarte Tautenburg

Tata Institute of Fundamental Research

E. Goffo

University of Turin

Thüringer Landessternwarte Tautenburg

D. Gandolfi

University of Turin

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

A. Hatzes

Thüringer Landessternwarte Tautenburg

G. Nowak

Nicolaus Copernicus University

A. Bonfanti

Institut fur Weltraumforschung

Allyson Bieryla

Harvard-Smithsonian Center for Astrophysics

William D. Cochran

The University of Texas at Austin

College of Natural Sciences

Karen A. Collins

Harvard-Smithsonian Center for Astrophysics

S. B. Fajardo-Acosta

California Institute of Technology (Caltech)

S.B. Howell

National Aeronautics and Space Administration (NASA)

Jon M. Jenkins

National Aeronautics and Space Administration (NASA)

Judith Korth

Lund University

J.H. Livingston

National Institutes of Natural Sciences

National Astronomical Observatory of Japan

The Graduate University for Advanced Studies (SOKENDAI)

Enric Palle

Instituto de Astrofísica de Canarias

University of La Laguna

Samuel N. Quinn

Harvard-Smithsonian Center for Astrophysics

R. Schwarz

Harvard-Smithsonian Center for Astrophysics

S. Seager

Massachusetts Institute of Technology (MIT)

Avi Shporer

Massachusetts Institute of Technology (MIT)

Keivan G. Stassun

Vanderbilt University

S. Striegel

SETI Institute

Vincent Van Eylen

University College London (UCL)

National Aeronautics and Space Administration (NASA)

Cristilyn N. Watkins

Harvard-Smithsonian Center for Astrophysics

J. N. Winn

Princeton University

C. Ziegler

Stephen F. Austin State University

Astronomy and Astrophysics

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

Vol. 697 A169

Subject Categories (SSIF 2025)

Astronomy, Astrophysics, and Cosmology

Meteorology and Atmospheric Sciences

DOI

10.1051/0004-6361/202453511

More information

Latest update

6/12/2025