TESS spots a mini- interior to a hot saturn in the TOI-2000 system

Lizhou Sha, Andrew M. Vanderburg, Chelsea X. Huang, David J. Armstrong, Rafael Brahm, Steven Giacalone, Mackenna L. Wood, Karen A. Collins, Louise D. Nielsen, Melissa J. Hobson, Carl Ziegler, Steve B. Howell, Pascal Torres-Miranda, Andrew W. Mann, George Zhou, Elisa Delgado-Mena, Felipe I. Rojas, Lyu Abe, Trifon Trifonov, Vardan AdibekyanSrgio G. Sousa, Sergio B. Fajardo-Acosta, Tristan Guillot, Saburo Howard, Colin Littlefield, Faith Hawthorn, François Xavier Schmider, Jan Eberhardt, Thiam Guan Tan, Ares Osborn, Richard P. Schwarz, Paul Strøm, Andrs Jordán, Gavin Wang, Thomas Henning, Bob Massey, Nicholas Law, Chris Stockdale, Elise Furlan, Gregor Srdoc, Peter J. Wheatley, David Barrado Navascus, Jack J. Lissauer, Keivan G. Stassun, George R. Ricker, Roland K. Vanderspek, David W. Latham, Joshua N. Winn, Sara Seager, Jon M. Jenkins, Thomas Barclay, Luke G. Bouma, Jessie L. Christiansen, Natalia Guerrero, Mark E. Rose

Research output: Contribution to journalArticlepeer-review


Hot jupiters are typically solitary around their stars, but a few have inner companion planets. Such companions provide insights into the formation history of hot jupiters. However, less is known about inner companions to hot Saturn-mass planets. The TOI-2000 system has been discovered, consisting of a hot Saturn-mass planet and a smaller inner companion. Specifically, TOI-2000 b is a mini-neptune in a 3.10-day orbit, while TOI-2000 c, the hot Saturn, is in a 9.13-day orbit. Both planets orbit the star TOI-2000, a metal-rich G dwarf located 173 pc away. The planets were observed by TESS and confirmed using various ground-based instruments. A new method using MIST stellar evolutionary tracks through Hamiltonian Monte Carlo was utilized, proving more efficient than the traditional method. Given their bright host star, both planets are prime candidates for atmospheric study by the JWST, which could reveal if they formed simultaneously or if TOI-2000 c influenced the formation of TOI-2000 b during migration.
Original languageEnglish
Pages (from-to)1113-1138
Number of pages26
JournalMonthly Notices of the Royal Astronomical Society
Issue number1
StatePublished - Sep 1 2023

ASJC Scopus Subject Areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


  • planets and satellites: detection
  • planets and satellites: formation
  • planets and satellites: gaseous planets
  • stars: individual: TOI-2000 (TIC 371188886)
  • techniques: photometric
  • techniques: radial velocities

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