[en] As the diversity of exoplanets continues to grow, it is important to revisit assumptions about habitability and classical habitable zone definitions. In this work, we introduce an expanded 'temperate' zone, defined by instellation fluxes in the range , thus encompassing a broader range of potentially habitable worlds. We also introduce the TEMPOS survey, which aims to produce a catalogue of precise radii for temperate planets orbiting M dwarfs with K. This work reports the discovery and characterization of two planets in this temperate regime orbiting mid-type M dwarfs: TOI-6716 b, a planet orbiting its M4 host star (, , ) with a period , and TOI-7384 b, a planet orbiting an M4 star every . The radii of TOI-6716 b and TOI-7384 b have precisions of 6.8 per cent and 5.9 per cent, respectively. We validate these planets with multiband ground-based photometric observations, high-resolution imaging, and statistical analyses. We find these planets to have instellation fluxes close to the inner (hotter) edge of the temperate zone, with and for TOI-6716 b and TOI-7384 b, respectively. Also, with a predicted transmission spectroscopy metric similar to the TRAPPIST-1 planets, TOI-6716 b is likely to be a good rocky-world James Webb Space Telescope target, should it have retained its atmosphere.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Scott, Madison G.; University of Birmingham, School of Physics and Astronomy
Dransfield, Georgina; University of Oxford, Department of Astrophysics, University of Oxford Magdalen College, University of Birmingham, School of Physics and Astronomy
Timmermans, Mathilde ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO) > Exoplanets in Transit: Identification and Characterization
Triaud, Amaury H. M. J.; University of Birmingham, School of Physics and Astronomy
Rackham, Benjamin V.; MIT, Department of Earth and Planetary Science, MIT, Center for Space Research/Kavli Institute
Barkaoui, Khalid ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO) > Exoplanets in Transit: Identification and Characterization
Burgasser, Adam J.; Department of Astronomy &, Astrophysics, UC San Diego, La Jolla, CA 92039, USA,
Collins, Karen A.; Harvard Smithsonian Center for Astrophysics
Gillon, Michaël ; Université de Liège - ULiège > Département d'astrophysique, géophysique et océanographie (AGO)
Howell, Steve B.; NASA Ames Research Center
Levine, Alan M.; MIT, Center for Space Research/Kavli Institute
Pozuelos, Francisco J.; Institute of Astrophysics of Andalusia
Stassun, Keivan G.; Vanderbilt University, Department of Physics and Astronomy
Ziegler, Carl; Stephen F Austin State University, Texas
Chew, Yilen Gomez Maqueo; UNAM, Institute of Astronomy
Clark, Catherine A.; Infrared Processing and Analysis Center
Davis, Yasmin; University of Birmingham, School of Physics and Astronomy
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