Year: 2023
Type: article
Abstract: ABSTRACT A new generation of observatories is enabling detailed study of exoplanetary atmospheres and the diversity of alien climates, allowing us to seek evidence for extraterrestrial biological and geological processes. Now is therefore the time to identify the most unique planets to be characterized with these instruments. In this context, we report on the discovery and validation of TOI-715 b, a $R_{\rm b}=1.55\pm 0.06\rm R_{\oplus }$ planet orbiting its nearby (42 pc) M4 host (TOI-715/TIC 271971130) with a period $P_{\rm b} = 19.288004_{-0.000024}^{+0.000027}$ d. TOI-715 b was first identified by TESS and validated using ground-based photometry, high-resolution imaging and statistical validation. The planet’s orbital period combined with the stellar effective temperature $T_{\rm eff}=3075\pm 75~\rm K$ give this planet an installation $S_{\rm b} = 0.67_{-0.20}^{+0.15}~\rm S_\oplus$, placing it within the most conservative definitions of the habitable zone for rocky planets. TOI-715 b’s radius falls exactly between two measured locations of the M-dwarf radius valley; characterizing its mass and composition will help understand the true nature of the radius valley for low-mass stars. We demonstrate TOI-715 b is amenable for characterization using precise radial velocities and transmission spectroscopy. Additionally, we reveal a second candidate planet in the system, TIC 271971130.02, with a potential orbital period of $P_{02} = 25.60712_{-0.00036}^{+0.00031}$ d and a radius of $R_{02} = 1.066\pm 0.092\, \rm R_{\oplus }$, just inside the outer boundary of the habitable zone, and near a 4:3 orbital period commensurability. Should this second planet be confirmed, it would represent the smallest habitable zone planet discovered by TESS to date.
Authors: Georgina Dransfield, Mathilde Timmermans, Amaury H M J Triaud, Martín Dévora-Pajares, Christian Aganze, Khalid Barkaoui, Adam J Burgasser, Karen A Collins, Marion Cointepas, Elsa Ducrot, Maximilian N Günther, Steve B Howell, Catriona A Murray, Prajwal Niraula, Benjamin V Rackham, Daniel Sebastian, Keivan G Stassun, Sebastián Zúñiga-Fernández, José Manuel Almenara, Xavier Bonfils, François Bouchy, Christopher J Burke, David Charbonneau, Jessie L Christiansen, Laetitia Delrez, Tianjun Gan, Lionel J García, Michaël Gillon, Yilen Gómez Maqueo Chew, Katharine M Hesse, Matthew J Hooton, Giovanni Isopi, Emmanuël Jehin, Jon M Jenkins, David W Latham, Franco Mallia, Felipe Murgas, Peter P Pedersen, Francisco J Pozuelos, Didier Queloz, David R Rodriguez, Nicole Schanche, Sara Seager, Gregor Srdoc, Chris Stockdale, Joseph D Twicken, Roland Vanderspek, Robert Wells, Joshua N Winn, Julien de Wit, Aldo Zapparata
Institutions: University of Birmingham, University of Liège, Universidad de Granada, University of California San Diego, Instituto de Astrofísica de Canarias, Massachusetts Institute of Technology, Center for Astrophysics Harvard & Smithsonian, University of Geneva, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, Université Grenoble Alpes, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, Astrophysique, Instrumentation et Modélisation, European Space Agency, European Space Research and Technology Centre, Ames Research Center, University of Colorado Boulder, Vanderbilt University, California Institute of Technology, NASA Exoplanet Science Institute, Tsinghua University, Universidad Nacional Autónoma de México, Regione Lazio, Universidad de La Laguna, Instituto de Astrofísica de Andalucía, Space Telescope Science Institute, University of Bern, Center for Space and Habitability, University of Maryland, College Park, Goddard Space Flight Center, Search for Extraterrestrial Intelligence, Princeton University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,873
Funders: National Science Foundation, National Aeronautics and Space Administration, Simons Foundation, Albert Ellis Institute, California Institute of Technology, Space Telescope Science Institute, European Space Agency, European Commission, Agence Nationale de la Recherche, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Fonds De La Recherche Scientifique - FNRS, Fédération Wallonie-Bruxelles, Ministry of Science, ICT and Future Planning, Korea Astronomy and Space Science Institute, Centre National de la Recherche Scientifique, Ministério da Ciência, Tecnologia, Inovações e Comunicações, Agencia Nacional de Investigación y Desarrollo, Ames Research Center, Goddard Space Flight Center, Science Mission Directorate, Science and Technology Facilities Council, Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture, Agencia Estatal de Investigación, H2020 European Research Council, FP7 Ideas: European Research Council
Awards: G101150294, G13101216, G154660318, G1853635042, G201248631, Red-enhanced cameras to seek rocky planets transiting Ultra-Cool Dwarfs, G2262748287, G3106129878, G3207356259, Exoplanets in Transit and their Atmosphere, G3480869486, G3681454997, G39620777, G4030817349, G4042783231, G4126913923, G4252671623, G425668148, G4334099265, G434337789, G4442677895, G4526231891, G4623258783, G463062595, G4757599054, G5537318980, G5795665120, G5894067328, G6201089904, G623270878, G6693794689, G6866600364, G6877505945, G6885269781, G7084143925, G7303466041, G7370930324, G7518687652, G7550253023, G7553243680, G7576874667, G8211471405, Innovative strategies for observing and modelling natural systems, Alexander von Humboldt and the Globalization of Science: Networks of Knowledge between Germany and the United States in the 19th Century, Running costs of the Ganymede Telescope., G8597195001, G878044590, G896728979
OpenAlex ID: W4377014189