Giant Outer Transiting Exoplanet Mass (GOT'EM) survey VII. TOI-6041: A multi-planet system including a warm Neptune exhibiting strong transit-timing variations
Journal article, 2026

We present the characterisation of the TOI-6041 system, a bright (V = 9.84 +/- 0.03) G7-type star hosting at least two planets. The inner planet, TOI-6041 b, is a warm Neptune with a radius of 4.55(-0.17)(+0.18)R(circle plus), initially identified as a single-transit event in TESS photometry. Subsequent observations with TESS and CHEOPS revealed additional transits, enabling the determination of its 26.04945(-0.00034)(+0.00033) orbital period and the detection of significant transit-timing variations (TTVs), exhibiting a peak-to-peak amplitude of about 1 hour. Radial-velocity (RV) measurements obtained with the APF spectrographs allowed us to place a 3 sigma upper mass limit of 28.9 M-circle plus on TOI-6041 b. In addition, the RV data reveal a second companion, TOI-6041 c, on an 88 d orbit, with a minimum mass of 0.25 M-Jup. A preliminary TTV analysis suggested that the observed variations could be caused by gravitational perturbations from planet c; however, reproducing the observed amplitudes requires a relatively high eccentricity of about 0.3 for that planet. Our dynamical stability analysis indicates that such a configuration is dynamically viable and places a 1 sigma upper limit on the mass of TOI-6041 c at 0.8 M-Jup. An alternative is the presence of a third, low-mass planet located between planets b and c, or on an inner orbit relative to planet b - particularly near a mean-motion resonance with planet b - which could account for the observed variations. These findings remain tentative, and further RV and photometric observations are essential in to better constrain the mass of planet b and to refine the TTV modeling, thereby improving our understanding of the system's dynamical architecture.

planets and satellites: detection

planets and satellites: dynamical evolution and stability

Author

N. Heidari

Inst Astrophys Paris

Sorbonne University

A. Alnajjarine

Sorbonne University

H. P. Osborn

University of Bern

Swiss Federal Institute of Technology in Zürich (ETH)

D. Dragomir

University of New Mexico

P. Dalba

University of California

W. Benz

University of Bern

G. Hebrard

Inst Astrophys Paris

Aix Marseille University

Sorbonne University

J. Laskar

Sorbonne University

N. Billot

University of Geneva

M. N. Gunther

European Space Agency (ESA)

T. G. Wilson

The University of Warwick

Y. Alibert

University of Bern

A. Bonfanti

Austrian Academy of Sciences

A. Bieryla

Harvard-Smithsonian Center for Astrophysics

C. Broeg

University of Bern

A. C. M. Correia

University of Coimbra

J. A. Egger

University of Bern

Z. Essack

University of New Mexico

E. Furlan

California Institute of Technology (Caltech)

D. Gandolfi

University of Turin

N. Grieves

University of Geneva

S. Howell

National Aeronautics and Space Administration (NASA)

D. LaCourse

Amateur Astronomer, 7507 52nd Pl NE

C. Pezzotti

University of Liège

T. Pritchard

National Aeronautics and Space Administration (NASA)

S. G. Sousa

University of Porto

S. Ulmer-Moll

Leiden University

University of Liège

S. Villanueva

National Aeronautics and Space Administration (NASA)

R. Alonso

Instituto de Astrofísica de Canarias

University of La Laguna

J. Asquier

European Space Agency (ESA)

T. Barczy

Admatis

D. Barrado

Spanish National Research Council (CSIC)

S. C. C. Barros

University of Porto

W. Baumjohann

Austrian Academy of Sciences

L. Borsato

Istituto nazionale di astrofisica (INAF)

A. Brandeker

Stockholm University

M. Buder

German Aerospace Center (DLR)

A. Collier Cameron

University of St Andrews

S. Csizmadia

German Aerospace Center (DLR)

P. E. Cubillos

Istituto nazionale di astrofisica (INAF)

Austrian Academy of Sciences

M. B. Davies

Lund University

M. Deleuil

Aix Marseille University

X. Delfosse

Grenoble Alpes University

A. Deline

University of Geneva

O. D. S. Demangeon

University of Porto

B. Demory

University of Bern

A. Derekas

Eötvös Loránd University (ELTE)

B. Edwards

Netherlands Institute for Space Research (SRON)

D. Ehrenreich

University of Geneva

A. Erikson

German Aerospace Center (DLR)

A. Fortier

University of Bern

L. Fossati

Austrian Academy of Sciences

Malcolm Fridlund

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

K. Gazeas

National and Kapodistrian University of Athens

M. Gillon

University of Liège

M. Gudel

University of Vienna

J. Hasiba

Austrian Academy of Sciences

A. Heitzmann

University of Geneva

C. Helling

Austrian Academy of Sciences

Technische Universität Graz

J. M. Jenkins

National Aeronautics and Space Administration (NASA)

T. Keller

University of Bern

S. R. Kane

University of California

K. G. Stassun

Vanderbilt University

L. L. Kiss

Eötvös Loránd University (ELTE)

Hungarian Academy of Sciences

J. Korth

University of Geneva

K. W. F. Lam

German Aerospace Center (DLR)

D. W. Latham

Harvard-Smithsonian Center for Astrophysics

A. Lecavelier des Etangs

Pierre and Marie Curie University (UPMC)

A. Leleu

University of Geneva

University of Bern

M. Lendl

University of Geneva

P. F. L. Maxted

Keele University

S. McDermott

Proto Logic LLC, 1718 Euclid St NW

B. Merin

European Space Agency (ESA)

C. Mordasini

University of Bern

V. Nascimbeni

Istituto nazionale di astrofisica (INAF)

G. Nowak

Nicolaus Copernicus University (SGMK)

G. Olofsson

Stockholm University

I. Pagano

Istituto nazionale di astrofisica (INAF)

E. Palle

University of La Laguna

Instituto de Astrofísica de Canarias

G. Piotto

University of Padua

Istituto nazionale di astrofisica (INAF)

D. Pollacco

The University of Warwick

D. Queloz

University of Cambridge

Swiss Federal Institute of Technology in Zürich (ETH)

R. Ragazzoni

Istituto nazionale di astrofisica (INAF)

University of Padua

H. Rauer

Freie Universität Berlin

German Aerospace Center (DLR)

I. Ribas

Inst Estudis Espacials Catalunya IEEC

Spanish National Research Council (CSIC)

G. Ricker

Massachusetts Institute of Technology (MIT)

N. C. Santos

University of Porto

G. Scandariato

Istituto nazionale di astrofisica (INAF)

S. Seager

Massachusetts Institute of Technology (MIT)

D. Segransan

University of Geneva

A. E. Simon

University of Bern

A. M. S. Smith

German Aerospace Center (DLR)

M. Stalport

University of Liège

S. Striegel

SETI Institute

National Aeronautics and Space Administration (NASA)

S. Sulis

Aix Marseille University

G. M. Szabo

Eötvös Loránd University (ELTE)

S. Udry

University of Geneva

V. Van Grootel

University of Liège

R. Vanderspek

Massachusetts Institute of Technology (MIT)

J. Venturini

University of Geneva

E. Villaver

University of La Laguna

Instituto de Astrofísica de Canarias

V. Viotto

Istituto nazionale di astrofisica (INAF)

N. A. Walton

University of Cambridge

J. N. Winn

Princeton University

S. Wolf

Istituto nazionale di astrofisica (INAF)

Astronomy and Astrophysics

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

Vol. 707 A134

Subject Categories (SSIF 2025)

Astronomy, Astrophysics, and Cosmology

DOI

10.1051/0004-6361/202556700

More information

Latest update

4/9/2026 9