TOI-530b: a giant planet transiting an M-dwarf detected by TESS

Tianjun Gan, Zitao Lin, Sharon Xuesong Wang, Shude Mao, Pascal Fouqué, Jiahao Fan, Megan Bedell, Keivan G. Stassun, Steven Giacalone, Akihiko Fukui, Felipe Murgas, David R. Ciardi, Steve B. Howell, Karen A. Collins, Avi Shporer, Luc Arnold, Thomas Barclay, David Charbonneau, Jessie Christiansen, Ian J.M. CrossfieldCourtney D. Dressing, Ashley Elliott, Emma Esparza-Borges, Phil Evans, Crystal L. Gnilka, Erica J. Gonzales, Andrew W. Howard, Keisuke Isogai, Kiyoe Kawauchi, Seiya Kurita, Beibei Liu, John H. Livingston, Rachel A. Matson, Norio Narita, Enric Palle, Hannu Parviainen, Benjamin V. Rackham, David R. Rodriguez, Mark Rose, Alexander Rudat, Joshua E. Schlieder, Nicholas J. Scott, Michael Vezie, George R. Ricker, Roland Vanderspek, David W. Latham, Sara Seager, Joshua N. Winn, Jon M. Jenkins

Research output: Contribution to journalArticlepeer-review

23 Scopus citations


We report the discovery of TOI-530b, a transiting Saturn-like planet around an M0.5V dwarf, delivered by the Transiting Exoplanet Survey Satellite (TESS). The host star is located at a distance of 147.7 ± 0.6 pc with a radius of R∗ = 0.54 ± 0.03 R⊙ and a mass of M∗ = 0.53 ± 0.02 M⊙. We verify the planetary nature of the transit signals by combining ground-based multiwavelength photometry, high-resolution spectroscopy from SPIRou as well as high-angular-resolution imaging. With V = 15.4 mag, TOI-530b is orbiting one of the faintest stars accessible by ground-based spectroscopy. Our model reveals that TOI-530b has a radius of 0.83 ± 0.05 RJ and a mass of 0.37 ± 0.08 MJ on a 6.39-d orbit. TOI-530b is the sixth transiting giant planet hosted by an M-type star, which is predicted to be infrequent according to core accretion theory, making it a valuable object to further study the formation and migration history of similar planets. Furthermore, we identify a potential dearth of hot massive giant planets around M-dwarfs with separation distance smaller than 0.1 au and planet-to-star mass ratio between 2 × 10-3 and 10-2. We also find a possible correlation between hot giant planet formation and the metallicity of its parent M-dwarf. We discuss the potential formation channel of such systems.

Original languageEnglish (US)
Pages (from-to)83-99
Number of pages17
JournalMonthly Notices of the Royal Astronomical Society
Issue number1
StatePublished - Mar 1 2022

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science


  • planets and satellites: detection
  • planets and satellites: gaseous planets
  • planets and satellites: individual: TIC 387690507, TOI 530
  • stars: low-mass


Dive into the research topics of 'TOI-530b: a giant planet transiting an M-dwarf detected by TESS'. Together they form a unique fingerprint.

Cite this