A joint effort to discover and characterize two resonant mini-Neptunes around TOI-1803 with TESS, HARPS-N, and CHEOPS
Artikel i vetenskaplig tidskrift, 2025

Context. The discovery and characterization of mini-Neptunes hold a potentially crucial impact on planetary formation and evolution theories. Estimating their orbital parameters and atmospheric properties would provide valuable hints to improve formation and atmospheric models. Aims. We present the discovery of two mini-Neptunes near a 2:1 orbital resonance configuration orbiting the K0 star TOI-1803. We describe in detail their orbital architecture and suggest some possible formation and evolution scenarios. Methods. Using CHEOPS, TESS, and HARPS-N datasets, we estimated the radius and the mass of both planets. We used a multidimensional Gaussian process with a quasi-periodic kernel to disentangle the planetary components from the stellar activity in the HARPS-N dataset. We performed dynamical modeling to explain the orbital configuration and performed planetary formation and evolution simulations. For the least dense planet, we assumed different atmospheric compositions and defined possible atmospheric scenarios with simulated JWST observations. Results. TOI-1803 b and TOI-1803 c have orbital periods of ∼6.3 and ∼12.9 days, respectively, residing in close proximity to a 2:1 orbital resonance. Ground-based photometric follow-up observations have revealed significant transit timing variations (TTV) with an amplitude of ∼10 min and ∼40 min, respectively, for planets b and -c. With the masses computed from the radial velocities dataset, we obtained a density of (0.39 ± 0.10) ρ⊕ and (0.076 ± 0.038) ρ⊕ for planets b and -c, respectively. TOI-1803 c is among the least dense mini-Neptunes currently known, and due to its inflated atmosphere, it is a suitable target for transmission spectroscopy with JWST. With NIRSpec observations, we could understand whether the planet has kept its primary atmosphere or not, which would constrain our formation models. Conclusions. We report the discovery of two mini-Neptunes close to a 2:1 orbital resonance. The detection of significant TTVs from ground-based photometry opens scenarios for a more precise mass determination. TOI-1803 c is one of the least dense mini-Neptunes known so far, and it is of great interest among the scientific community since it could constrain current formation scenarios. JWST observations could give us valuable insights to characterize this interesting system.

Planets and satellites: formation

Planets and satellites: detection

Planets and satellites: dynamical evolution and stability

Planets and satellites: fundamental parameters

Planets and satellites: interiors

Författare

Tiziano Zingales

Università di Padova

Luca Malavolta

Università di Padova

Luca Borsato

Istituto nazionale di astrofisica (INAF)

Diego Turrini

Istituto nazionale di astrofisica (INAF)

Andrea Bonfanti

Institut fur Weltraumforschung

Danae Polychroni

Osservatorio Astronomico di Trieste

Giacomo Mantovan

Università di Padova

Domenico Nardiello

Università di Padova

Valerio Nascimbeni

Istituto nazionale di astrofisica (INAF)

Antonino Francesco Lanza

Istituto nazionale di astrofisica (INAF)

Anja Bekkelien

Université de Genève

Alessandro Sozzetti

Istituto nazionale di astrofisica (INAF)

Christopher Broeg

Universität Bern

Luca Naponiello

Istituto nazionale di astrofisica (INAF)

Monika Lendl

Université de Genève

Aldo Stefano Bonomo

Istituto nazionale di astrofisica (INAF)

Attila E. Simon

Universität Bern

Silvano Desidera

Istituto nazionale di astrofisica (INAF)

Giampaolo Piotto

Università di Padova

Luigi Mancini

Universita degli Studi di Roma Tor Vergata

Matthew J. Hooton

University of Cambridge

Andrea Bignamini

Osservatorio Astronomico di Trieste

Jo Ann Egger

Universität Bern

Antonio Maggio

Istituto nazionale di astrofisica (INAF)

Yann Alibert

Universität Bern

Daniele Locci

Istituto nazionale di astrofisica (INAF)

Laetitia Delrez

Universite de Liège

Federico Biassoni

Universita degli Studi dell'Insubria

Luca Fossati

Institut fur Weltraumforschung

Lorenzo Cabona

Istituto nazionale di astrofisica (INAF)

Gaia Lacedelli

Instituto de Astrofísica de Canarias

Ilaria Carleo

Instituto de Astrofísica de Canarias

Pietro Leonardi

Università di Padova

Gloria Andreuzzi

Osservatorio Astronomico di Roma

Alexis Brandeker

Stockholms universitet

Rosario Cosentino

Istituto nazionale di astrofisica (INAF)

Alexandre C. M. Correia

Universidade de Coimbra

Riccardo Claudi

Istituto nazionale di astrofisica (INAF)

Roi Alonso

Instituto de Astrofísica de Canarias

Mario Damasso

Istituto nazionale di astrofisica (INAF)

Thomas G. Wilson

The University of Warwick

Tamás Bárczy

Admatis

Matteo Pinamonti

Istituto nazionale di astrofisica (INAF)

David Baker

Austin College

Khalid Barkaoui

Universite de Liège

David Barrado Navascués

Europeiska rymdorganisationen (ESA)

Susana Barros

Universidade do Porto

Wolfgang Baumjohann

Institut fur Weltraumforschung

Thomas Beck

Universität Bern

Charles A. Beichman

National Aeronautics and Space Administration (NASA)

Willy Benz

Universität Bern

Allyson Bieryla

Harvard-Smithsonian Center for Astrophysics

Nicolas Billot

Université de Genève

Pau Bosch-Cabot

Observatori Astronòmic Albanya

Luke Bouma

California Institute of Technology (Caltech)

David Ciardi

National Aeronautics and Space Administration (NASA)

Andrew Cameron

University of St Andrews

Karen Collins

Harvard-Smithsonian Center for Astrophysics

Ian J. M. Crossfield

University of Kansas

Szilard Csizmadia

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Patricio Cubillos

Institut fur Weltraumforschung

Melvyn Davies

Lunds universitet

Magali Deleuil

Laboratoire d'Astrophysique de Marseille

Adrien Deline

Université de Genève

Olivier Demangeon

Universidade do Porto

Brice-Olivier Demory

Universität Bern

Aliz Derekas

Eötvös Loránd University (ELTE)

Diana Dragomir

University of New Mexico

Billy Edwards

Netherlands Institute for Space Research (SRON)

David Ehrenreich

Université de Genève

Anders Erikson

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Ben Falk

Space Telescope Science Institute (STScI)

Andrea Fortier

Universität Bern

Malcolm Fridlund

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Universiteit Leiden

Akihiko Fukui

Instituto de Astrofísica de Canarias

Davide Gandolfi

Universita degli Studi di Torino

Kosmas Gazeas

University of Athens

Michaël Gillon

Universite de Liège

Erica J. Gonzales

University of California

Manuel Guedel

Universität Wien

Pere Guerra

Observatori Astronòmic Albanya

Maximilian N. Günther

Europeiska rymdorganisationen (ESA)

Alexis Heitzmann

Université de Genève

Ch. Helling

Institut fur Weltraumforschung

Steve B. Howell

National Aeronautics and Space Administration (NASA)

Kate Isaak

Europeiska rymdorganisationen (ESA)

Jon Jenkins

National Aeronautics and Space Administration (NASA)

Laszlo Kiss

Magyar Tudomanyos Akademia

Judith Korth

Lunds universitet

Kristine Wai Fun Lam

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Jacques Laskar

Observatoire de Paris

Alain Lecavelier des Etangs

Institut d 'Astrophysique de Paris

Demetrio Magrin

Istituto nazionale di astrofisica (INAF)

Rachel Matson

National Aeronautics and Space Administration (NASA)

Elisabeth Matthews

Max-Planck-Gesellschaft

Pierre Maxted

Keele University

Scott McDermott

Protologic LLC

Matteo Munari

Istituto nazionale di astrofisica (INAF)

Christoph Mordasini

Universität Bern

Norio Narita

Instituto de Astrofísica de Canarias

Göran Olofsson

Stockholms universitet

Roland Ottensamer

Universität Wien

Isabella Pagano

Istituto nazionale di astrofisica (INAF)

Enric Palle

Instituto de Astrofísica de Canarias

Gisbert Peter

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Donald L. Pollacco

The University of Warwick

Didier Queloz

University of Cambridge

Roberto Ragazzoni

Università di Padova

Nicola Rando

Europeiska rymdorganisationen (ESA)

Francesco Ratti

Europeiska rymdorganisationen (ESA)

Heike Rauer

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Ignasi Ribas

Consejo Superior de Investigaciones Científicas (CSIC)

Sébastien Salmon

Université de Genève

Nuno Santos

Universidade do Porto

Gaetano Scandariato

Istituto nazionale di astrofisica (INAF)

Sara Seager

Massachusetts Institute of Technology (MIT)

Damien Ségransan

Université de Genève

Alexis M. S. Smith

Deutsches Zentrums für Luft- und Raumfahrt (DLR)

Joshua E. Schlieder

National Aeronautics and Space Administration (NASA)

Richard Schwarz

Harvard-Smithsonian Center for Astrophysics

Avi Shporer

Massachusetts Institute of Technology (MIT)

S. G. Sousa

Universidade do Porto

Manu Stalport

Universite de Liège

M. Steinberger

Institut fur Weltraumforschung

Sophia Sulis

Laboratoire d'Astrophysique de Marseille

Gyula Szabó

Eötvös Loránd University (ELTE)

Joseph Twicken

National Aeronautics and Space Administration (NASA)

Stephane Udry

Université de Genève

Valerie Van Grootel

Universite de Liège

Julia Venturini

Université de Genève

Eva Villaver

Instituto de Astrofísica de Canarias

Nicholas Walton

University of Cambridge

Joshua N. Winn

Princeton University

Astronomy and Astrophysics

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

Vol. 695 A273

Ämneskategorier (SSIF 2025)

Astronomi, astrofysik och kosmologi

DOI

10.1051/0004-6361/202451180

Mer information

Senast uppdaterat

2025-04-23