TY - JOUR
T1 - A 1.55 R⨁ habitable-zone planet hosted by TOI-715, an M4 star near the ecliptic South Pole
AU - Dransfield, Georgina
AU - Timmermans, Mathilde
AU - Triaud, Amaury H. M. J.
AU - Dévora-Pajares, Martín
AU - Aganze, Christian
AU - Barkaoui, Khalid
AU - Burgasser, Adam J.
AU - Collins, Karen A.
AU - Cointepas, Marion
AU - Ducrot, Elsa
AU - Günther, Maximilian N.
AU - Howell, Steve B.
AU - Murray, Catriona A.
AU - Niraula, Prajwal
AU - Rackham, Benjamin V.
AU - Sebastian, Daniel
AU - Stassun, Keivan G.
AU - Zúñiga-Fernández, Sebastián
AU - Almenara, José Manuel
AU - Bonfils, Xavier
AU - Bouchy, François
AU - Burke, Christopher J.
AU - Charbonneau, David
AU - Christiansen, Jessie L.
AU - Delrez, Laetitia
AU - Gan, Tianjun
AU - García, Lionel J.
AU - Gillon, Michaël
AU - Chew, Yilen Gómez Maqueo
AU - Hesse, Katharine M.
AU - Hooton, Matthew J.
AU - Isopi, Giovanni
AU - Jehin, Emmanuël
AU - Jenkins, Jon M.
AU - Latham, David W.
AU - Mallia, Franco
AU - Murgas, Felipe
AU - Pedersen, Peter P.
AU - Pozuelos, Francisco J.
AU - Queloz, Didier
AU - Rodriguez, David R.
AU - Schanche, Nicole
AU - Seager, Sara
AU - Srdoc, Gregor
AU - Stockdale, Chris
AU - Twicken, Joseph D.
AU - Vanderspek, Roland
AU - Wells, Robert
AU - Winn, Joshua N.
AU - Wit, Julien de
AU - Zapparata, Aldo
PY - 2023/5/18
Y1 - 2023/5/18
N2 - 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 characterised with these instruments. In this context, we report on the discovery and validation of TOI-715 b, a Rb=1.55±0.06R⊕ planet orbiting its nearby (42 pc) M4 host (TOI-715/TIC 271971130) with a period Pb=19.288004+0.000027−0.000024 days. 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 Teff=3075±75 K give this planet an instellation Sb=0.67+0.15−0.20 S⊕ , 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; characterising 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 characterisation 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 P02=25.60712+0.00031−0.00036 days and a radius of R02=1.066±0.092R⊕ , 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.
AB - 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 characterised with these instruments. In this context, we report on the discovery and validation of TOI-715 b, a Rb=1.55±0.06R⊕ planet orbiting its nearby (42 pc) M4 host (TOI-715/TIC 271971130) with a period Pb=19.288004+0.000027−0.000024 days. 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 Teff=3075±75 K give this planet an instellation Sb=0.67+0.15−0.20 S⊕ , 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; characterising 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 characterisation 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 P02=25.60712+0.00031−0.00036 days and a radius of R02=1.066±0.092R⊕ , 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.
KW - astro-ph.EP
KW - exoplanets
KW - planets and satellites: detection
KW - planets and satellites: terrestrial planets
KW - planets and satellites: fundamental parameter
UR - https://www.scopus.com/pages/publications/85165657990
U2 - 10.1093/mnras/stad1439
DO - 10.1093/mnras/stad1439
M3 - Article
SN - 0035-8711
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
M1 - stad1439
ER -