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
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
U2 - 10.3847/1538-3881/ad4993
DO - 10.3847/1538-3881/ad4993
M3 - Article
SN - 0004-6256
VL - 168
JO - The Astronomical Journal
JF - The Astronomical Journal
IS - 1
M1 - 41
ER -