Mass determination of the three long-period Neptune- and sub-Neptune-sized planets transiting TOI-282
Artikel i vetenskaplig tidskrift, 2025
TOI-282 is a bright (V = 9.38) F8 main-sequence star known to host three transiting long-period (Pb = 22.9 d, Pc = 56.0 d, and Pd = 84.3 d) small (Rp ≈ 2-4 R⊕) planets. The orbital period ratio of the two outermost planets, namely TOI-282 c and d, is close to the 3:2 commensurability, suggesting that the planets might be trapped in a mean motion resonance. We combined space-borne photometry from the TESS telescope with high-precision HARPS and ESPRESSO Doppler measurements to refine orbital parameters, measure the planetary masses, and investigate the architecture and evolution of the system. We performed a Markov chain Monte Carlo joint analysis of the transit light curves and radial velocity time series, and carried out a dynamical analysis to model transit timing variations and Doppler measurements along with N-body integration. In agreement with previous results, we found that TOI-282 b, c, and d have radii of Rb = 2.69 ± 0.23 R⊕, Rc = 4.13-0.14+0.16 R⊕, and Rd = 3.11 ± 0.15 R⊕, respectively. We measured planetary masses of Mb = 6.2 ± 1.6 M⊕, Mc = 9.2 ± 2.0 M⊕, and Md = 5.8-1.1+0.9 M⊕, which imply mean densities of ρb = 1.8-0.6+0.7 g cm-3, ρc = 0.7 ± 0.2 g cm-3, and ρd = 1.1-0.2+0.3 g cm-3, respectively. The three planets may be water worlds, making TOI-282 an interesting system for future atmospheric follow-up observations with JWST and ELT.
Planets and satellites: general
Planets and satellites: fundamental parameters
Planets and satellites: dynamical evolution and stability
Planets and satellites: physical evolution
Planets and satellites: composition
Författare
A. Barone
Universita degli Studi di Torino
Institut fur Weltraumforschung
F. Rodler
European Southern Observatory Santiago
D. Gandolfi
Universita degli Studi di Torino
A. Bonfanti
Institut fur Weltraumforschung
P. Leonardi
Università di Padova
Universita degli Studi di Trento
L. Visca
Universita degli Studi di Torino
Malcolm Fridlund
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
Universiteit Leiden
M. Brogi
Universita degli Studi di Torino
Istituto nazionale di astrofisica (INAF)
L. Fossati
Institut fur Weltraumforschung
P. E. Cubillos
Institut fur Weltraumforschung
Istituto nazionale di astrofisica (INAF)
William D. Cochran
University of Texas
Szilard Csizmadia
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
J.H. Livingston
National Institutes of Natural Sciences
National Astronomical Observatory of Japan
The Graduate University for Advanced Studies (SOKENDAI)
G. Nowak
Uniwersytet Mikolaja Kopernika
Enric Palle
Instituto de Astrofísica de Canarias
Universidad de la Laguna
Carina Persson
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
S. Redfield
Wesleyan University
H. Schmerling
Universität zu Köln
A. M.S. Smith
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 704 A41Ämneskategorier (SSIF 2025)
Astronomi, astrofysik och kosmologi
DOI
10.1051/0004-6361/202556791