The Astronomical Journal (Jan 2024)
TESS Hunt for Young and Maturing Exoplanets (THYME). X. A Two-planet System in the 210 Myr MELANGE-5 Association
- Pa Chia Thao,
- Andrew W. Mann,
- Madyson G. Barber,
- Adam L. Kraus,
- Benjamin M. Tofflemire,
- Jonathan L. Bush,
- Mackenna L. Wood,
- Karen A. Collins,
- Andrew Vanderburg,
- Samuel N. Quinn,
- George Zhou,
- Elisabeth R. Newton,
- Carl Ziegler,
- Nicholas Law,
- Khalid Barkaoui,
- Francisco J. Pozuelos,
- Mathilde Timmermans,
- Michaël Gillon,
- Emmanuël Jehin,
- Richard P. Schwarz,
- Tianjun Gan,
- Avi Shporer,
- Keith Horne,
- Ramotholo Sefako,
- Olga Suarez,
- Djamel Mekarnia,
- Tristan Guillot,
- Lyu Abe,
- Amaury H. M. J. Triaud,
- Don J. Radford,
- Ana Isabel Lopez Murillo,
- George R. Ricker,
- Joshua N. Winn,
- Jon M. Jenkins,
- Luke G. Bouma,
- Michael Fausnaugh,
- Natalia M. Guerrero,
- Michelle Kunimoto
Affiliations
- Pa Chia Thao
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]
- Andrew W. Mann
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]
- Madyson G. Barber
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]
- Adam L. Kraus
- ORCiD
- Department of Astronomy, The University of Texas at Austin , Austin, TX 78712, USA
- Benjamin M. Tofflemire
- ORCiD
- Department of Astronomy, The University of Texas at Austin , Austin, TX 78712, USA
- Jonathan L. Bush
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]
- Mackenna L. Wood
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]; Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Karen A. Collins
- ORCiD
- Center for Astrophysics ∣ Harvard & Smithsonian , 60 Garden Street, Cambridge, MA 02138, USA
- Andrew Vanderburg
- ORCiD
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Samuel N. Quinn
- ORCiD
- Center for Astrophysics ∣ Harvard & Smithsonian , 60 Garden Street, Cambridge, MA 02138, USA
- George Zhou
- ORCiD
- Centre for Astrophysics, University of Southern Queensland , West Street, Toowoomba, QLD 4350, Australia
- Elisabeth R. Newton
- ORCiD
- Department of Physics and Astronomy, Dartmouth College , Hanover, NH 03755, USA
- Carl Ziegler
- ORCiD
- Department of Physics, Engineering and Astronomy, Stephen F. Austin State University , 1936 North Street, Nacogdoches, TX 75962, USA
- Nicholas Law
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]
- Khalid Barkaoui
- ORCiD
- Astrobiology Research Unit, Université de Liège , 19C Allée du 6 Août, 4000 Liège, Belgium; Department of Earth, Atmospheric and Planetary Science, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Instituto de Astrofísica de Canarias (IAC) , Calle Vía Láctea s/n, 38200, La Laguna, Tenerife, Spain
- Francisco J. Pozuelos
- ORCiD
- Astrobiology Research Unit, Université de Liège , 19C Allée du 6 Août, 4000 Liège, Belgium; Instituto de Astrofísica de Andalucía (IAA-CSIC) , Glorieta de la Astronomía s/n, 18008 Granada, Spain
- Mathilde Timmermans
- ORCiD
- Astrobiology Research Unit, Université de Liège , 19C Allée du 6 Août, 4000 Liège, Belgium
- Michaël Gillon
- ORCiD
- Astrobiology Research Unit, Université de Liège , 19C Allée du 6 Août, 4000 Liège, Belgium
- Emmanuël Jehin
- ORCiD
- Space Sciences, Technologies and Astrophysics Research (STAR) Institute, Université de Liège , Allée du 6 Août 19C, B-4000 Liège, Belgium
- Richard P. Schwarz
- ORCiD
- Center for Astrophysics ∣ Harvard & Smithsonian , 60 Garden Street, Cambridge, MA 02138, USA
- Tianjun Gan
- ORCiD
- Department of Astronomy, Tsinghua University , Beijing 100084, People's Republic of China
- Avi Shporer
- ORCiD
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Keith Horne
- ORCiD
- SUPA Physics and Astronomy, University of St. Andrews , Fife, KY16 9SS Scotland, UK
- Ramotholo Sefako
- ORCiD
- South African Astronomical Observatory , P.O. Box 9, Observatory, Cape Town 7935, South Africa
- Olga Suarez
- ORCiD
- Université Côte d’Azur , Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice cedex 4, France
- Djamel Mekarnia
- ORCiD
- Université Côte d’Azur , Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice cedex 4, France
- Tristan Guillot
- ORCiD
- Université Côte d’Azur , Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice cedex 4, France
- Lyu Abe
- ORCiD
- Université Côte d’Azur , Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice cedex 4, France
- Amaury H. M. J. Triaud
- ORCiD
- School of Physics & Astronomy, University of Birmingham , Edgbaston, Birmingham, B15 2TT, UK
- Don J. Radford
- ORCiD
- Brierfield Observatory , New South Wales, Australia
- Ana Isabel Lopez Murillo
- ORCiD
- Department of Physics and Astronomy, The University of North Carolina at Chapel Hill , Chapel Hill, NC 27599, USA ; [email protected]
- George R. Ricker
- ORCiD
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- Joshua N. Winn
- ORCiD
- Department of Astrophysical Sciences, Princeton University , 4 Ivy Lane, Princeton, NJ 08544, USA
- Jon M. Jenkins
- ORCiD
- NASA Ames Research Center , Moffett Field, CA 94035, USA
- Luke G. Bouma
- ORCiD
- Department of Astrophysical Sciences, Princeton University , 4 Ivy Lane, Princeton, NJ 08544, USA
- Michael Fausnaugh
- ORCiD
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA; Department of Physics & Astronomy, Texas Tech University , Lubbock, TX 79410-1051, USA
- Natalia M. Guerrero
- ORCiD
- Department of Astronomy, University of Florida , Gainesville, FL 32811, USA
- Michelle Kunimoto
- ORCiD
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
- DOI
- https://doi.org/10.3847/1538-3881/ad4993
- Journal volume & issue
-
Vol. 168,
no. 1
p. 41
Abstract
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 ( T _eff = 3326 K) host star, these planets represent excellent candidates for atmospheric characterization with JWST.
Keywords
- Exoplanet astronomy
- Transit photometry
- Stellar ages
- Young star clusters
- Stellar activity
- Transit timing variation method
