TY - JOUR
T1 - TESS hunt for young and maturing exoplanets (THYME). X. A two-planet system in the 210 Myr MELANGE-5 association
AU - Thao, Pa Chia
AU - Mann, Andrew W.
AU - Barber, Madyson G.
AU - Kraus, Adam L.
AU - Tofflemire, Benjamin M.
AU - Bush, Jonathan L.
AU - Wood, Mackenna L.
AU - Collins, Karen A.
AU - Vanderburg, Andrew
AU - Quinn, Samuel N.
AU - Zhou, George
AU - Newton, Elisabeth R.
AU - Ziegler, Carl
AU - Law, Nicholas
AU - Barkaoui, Khalid
AU - Pozuelos, Francisco J.
AU - Timmermans, Mathilde
AU - Gillon, Michaël
AU - Jehin, Emmanuël
AU - Schwarz, Richard P.
AU - Gan, Tianjun
AU - Shporer, Avi
AU - Horne, Keith
AU - Sefako, Ramotholo
AU - Suarez, Olga
AU - Mekarnia, Djamel
AU - Guillot, Tristan
AU - Abe, Lyu
AU - Triaud, Amaury H. M. J.
AU - Radford, Don J.
AU - Lopez Murillo, Ana Isabel
AU - Ricker, George R.
AU - Winn, Joshua N.
AU - Jenkins, Jon M.
AU - Bouma, Luke G.
AU - Fausnaugh, Michael
AU - Guerrero, Natalia M.
AU - Kunimoto, Michelle
N1 - Funding: P.C.T. was supported by an NSF Graduate Research Fellowship (DGE-1650116), the NC Space Grant Graduate Research Fellowship, the Zonta International Amelia Earhart Fellowship, and the Jack Kent Cooke Foundation Graduate Scholarship. A.W.M. was supported by grants from the NSF
CAREER program (AST-2143763) and NASA’s exoplanet research program (XRP 80NSSC21K0393). M.G.B. was supported by an NSF Graduate Research Fellowship (DGE2040435) and the NC Space Grant Graduate Research
Fellowship. F.J.P. acknowledges financial support from the grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/
501100011033 and through projects PID2019-109522GB-C52
and PID2022-137241NB-C43.
This research also received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant
agreement No. 803193/BEBOP) and from the Science and Technology Facilities Council (STFC; grant No. ST/S00193X/1).
The postdoctoral fellowship of K.B. is funded by F.R.S.-FNRS grant T.0109.20 and by the Francqui Foundation. K.A.C. acknowledges support from the TESS mission via subaward s3449 from MIT. M.K. acknowledges support from the MIT
Kavli Institute as a Juan Carlos Torres Fellow.
This publication benefits from the support of the French Community of Belgium in the context of the FRIA Doctoral Grant awarded to M.T.
PY - 2024/7/1
Y1 - 2024/7/1
N2 - Young (<500 Myr) planets are critical to studying how planets form and evolve. Among these young planetary systems, multiplanet configurations are particularly useful, as they provide a means to control for variables within a system. Here, we report the discovery and characterization of a young planetary system, TOI-1224. We show that the planet host resides within a young population we denote as MELANGE-5. By employing a range of age-dating methods—isochrone fitting, lithium abundance analysis, gyrochronology, and Gaia excess variability—we estimate the age of MELANGE-5 to be 210 ± 27 Myr. MELANGE-5 is situated in close proximity to previously identified younger (80–110 Myr) associations, Crius 221 and Theia 424/Volans-Carina, motivating further work to map out the group boundaries. In addition to a planet candidate detected by the TESS pipeline and alerted as a TESS object of interest, TOI-1224 b, we identify a second planet, TOI-1224 c, using custom search tools optimized for young stars (Notch and LOCoR). We find that the planets are 2.10 ± 0.09 R⊕ and 2.88 ± 0.10 R⊕ and orbit their host star every 4.18 and 17.95 days, respectively. With their bright (K = 9.1 mag), small (R* = 0.44 R⊙), and cool (Teff = 3326 K) host star, these planets represent excellent candidates for atmospheric characterization with JWST.
AB - Young (<500 Myr) planets are critical to studying how planets form and evolve. Among these young planetary systems, multiplanet configurations are particularly useful, as they provide a means to control for variables within a system. Here, we report the discovery and characterization of a young planetary system, TOI-1224. We show that the planet host resides within a young population we denote as MELANGE-5. By employing a range of age-dating methods—isochrone fitting, lithium abundance analysis, gyrochronology, and Gaia excess variability—we estimate the age of MELANGE-5 to be 210 ± 27 Myr. MELANGE-5 is situated in close proximity to previously identified younger (80–110 Myr) associations, Crius 221 and Theia 424/Volans-Carina, motivating further work to map out the group boundaries. In addition to a planet candidate detected by the TESS pipeline and alerted as a TESS object of interest, TOI-1224 b, we identify a second planet, TOI-1224 c, using custom search tools optimized for young stars (Notch and LOCoR). We find that the planets are 2.10 ± 0.09 R⊕ and 2.88 ± 0.10 R⊕ and orbit their host star every 4.18 and 17.95 days, respectively. With their bright (K = 9.1 mag), small (R* = 0.44 R⊙), and cool (Teff = 3326 K) host star, these planets represent excellent candidates for atmospheric characterization with JWST.
KW - Stellar activity
KW - Transit timing variation method
KW - Exoplanet astronomy
KW - Stellar ages
KW - Young star clusters
KW - Transit photometry
UR - https://www.scopus.com/pages/publications/85197061480
U2 - 10.3847/1538-3881/ad4993
DO - 10.3847/1538-3881/ad4993
M3 - Article
SN - 0004-6256
VL - 168
JO - Astronomical Journal
JF - Astronomical Journal
IS - 1
M1 - 41
ER -