A giant planet transiting a 0.2 solar mass host star

A giant planet transiting a 0.2 solar mass host star
Edward M. Bryant, Andr’es Jord’an, Joel D. Hartman, Daniel Bayliss, Elyar Sedaghati, Khalid Barkaoui, Jamila Chouqar, Francisco J. Pozuelos, Daniel P. Thorngren, Mathilde Timmermans, Jose Manuel Almenara, Igor V. Chilingarian, Karen A. Collins, Tianjun Gan, Steve B. Howell, Norio Narita, Enric Palle, Benjamin V. Rackham, Amaury H. M. J. Triaud, Gaspar ‘A. Bakos, Rafael Brahm, Melissa J. Hobson, Vincent Van Eylen, Pedro J. Amado, Luc Arnold, Xavier Bonfils, Artem Burdanov, Charles Cadieux, Douglas A. Caldwell, Victor Casanova, David Charbonneau, Catherine A. Clark, Kevin I. Collins, Tansu Daylan, Georgina Dransfield, Brice-Oliver Demory, Elsa Ducrot, Gareb Fern’andez-Rodr’iguez, Izuru Fukuda, Akihiko Fukui, Micha"el Gillon, Rebecca Gore, Matthew J. Hooton, Kai Ikuta, Emmanuel Jehin, Jon M. Jenkins, Alan M. Levine, Colin Littlefield, Felipe Murgas, Kendra Nguyen, Hannu Parviainen, Didier Queloz, S. Seager, Daniel Sebastian, Gregor Srdoc, R. Vanderspek, Joshua N. Winn, Julien de Wit, Sebasti’an Z’u~niga-Fern’andez
arXiv:2506.07931v1 Announce Type: new
Abstract: Planet formation models suggest that the formation of giant planets is significantly harder around low-mass stars, due to the scaling of protoplanetary disc masses with stellar mass. The discovery of giant planets orbiting such low-mass stars thus imposes strong constraints on giant planet formation processes. Here, we report the discovery of a transiting giant planet orbiting a $0.207 pm 0.011 M_{odot}$ star. The planet, TOI-6894 b, has a mass and radius of $M_P = 0.168 pm 0.022 M_J (53.4 pm 7.1 M_{oplus})$ and $R_P = 0.855 pm 0.022 R_J$, and likely includes $12 pm 2 M_{oplus}$ of metals. The discovery of TOI-6894 b highlights the need for a better understanding of giant planet formation mechanisms and the protoplanetary disc environments in which they occur. The extremely deep transits (17% depth) make TOI-6894 b one of the most accessible exoplanetary giants for atmospheric characterisation observations, which will be key for fully interpreting the formation history of this remarkable system and for the study of atmospheric methane chemistry.arXiv:2506.07931v1 Announce Type: new
Abstract: Planet formation models suggest that the formation of giant planets is significantly harder around low-mass stars, due to the scaling of protoplanetary disc masses with stellar mass. The discovery of giant planets orbiting such low-mass stars thus imposes strong constraints on giant planet formation processes. Here, we report the discovery of a transiting giant planet orbiting a $0.207 pm 0.011 M_{odot}$ star. The planet, TOI-6894 b, has a mass and radius of $M_P = 0.168 pm 0.022 M_J (53.4 pm 7.1 M_{oplus})$ and $R_P = 0.855 pm 0.022 R_J$, and likely includes $12 pm 2 M_{oplus}$ of metals. The discovery of TOI-6894 b highlights the need for a better understanding of giant planet formation mechanisms and the protoplanetary disc environments in which they occur. The extremely deep transits (17% depth) make TOI-6894 b one of the most accessible exoplanetary giants for atmospheric characterisation observations, which will be key for fully interpreting the formation history of this remarkable system and for the study of atmospheric methane chemistry.