TOI-1080 b: a temperate, rocky planet orbiting a quiet M4V host

Gómez Maqueo Chew, Y.; Dransfield, G.; Barkaoui, K.; Cadieux, C.; Ducrot, E.; Rackham, B.V.; Timmermans, M.; Burgasser, A.J.; Segura, A.; Stassun, K.G.; Ziegler, C.; Soubkiou, A.; Almenara, J.M.; Demory, B.O.; Gillon, M.; Jenkins, J.M.; Jofré, E.; Khandelwal, A.; Páez, S.; Petrucci, R.; Parc, L.; Pichardo Marcano, M.; Plauchu-Frayn, I.; Schroffenegger, U.; Schwarz, R.; Tan, T.G.; Triaud, A.H.M.J.; Benkhaldoun, Z.; Bonfils, X.; Bouchy, F.; Collins, K.A.; Davoudi, F.; Doyon, R.; Gachaoui, M.; Hooton, M.J.; Jehin, E.; Pozuelos, F.J.; Scott, M.G.; Yalçınkaya, S.; Zong Lang, F.; Zúñiga-Fernández, S.; De Medeiros, J.R.; González-Hernández, J.I.; Santos, N.C.

doi:10.1093/mnras/stag438

TOI-1080 b: a temperate, rocky planet orbiting a quiet M4V host

Gómez Maqueo Chew Y., Dransfield G., Barkaoui K., Cadieux C., Ducrot E., Rackham B., ...More

Monthly Notices of the Royal Astronomical Society, vol.548, no.1, 2026 (SCI-Expanded, Scopus)

Publication Type: Article / Article
Volume: 548 Issue: 1
Publication Date: 2026
Doi Number: 10.1093/mnras/stag438
Journal Name: Monthly Notices of the Royal Astronomical Society
Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC, zbMATH, Directory of Open Access Journals
Keywords: exoplanets, planetary systems, stars: individual: TOI-1080, stars: low-mass, techniques: photometric, techniques: spectroscopic
Ankara University Affiliated: No

Abstract

We present the detection and validation of a small, temperate transiting exoplanet orbiting TOI-1080 every 3.9652482$_{-0.0000015}^{+0.0000014}$ d. The host is a quiet M4V star at 25.6 pc. The planet signal was first detected by the Transiting Exoplanet Survey Satellite (TESS) and validated using TESS and ground-based observations. By fitting the available light curves, the planet radius is measured to be 1.200 $\pm$ 0.058 R$_{\rm{\oplus }}$ and its equilibrium temperature of $368_{-10.}^{+12}$ K. With Near Infra Red Planet Searcher (NIRPS) radial velocities, we are able to place a 3$\sigma$ upper limit on the mass of TOI-1080 b of 10.7 M$_{\rm{\oplus }}$. Our injection-recovery tests enable us to discard additional transiting planets in the TOI-1080 system with radii down to 0.9 R$_{\rm{\oplus }}$ and periods between 0.5 and 7.7 d, and planets with radii larger than 1.4 R$_{\rm{\oplus }}$ for periods up to 19 d. We demonstrate that it is highly amenable to characterization of its mass and putative atmosphere. In particular, we find that TOI-1080 b is an exceptional target for the ongoing JWST + HST Rocky Worlds DDT programme, having a priority score that is higher than four out of nine targets currently being investigated by the programme. TOI-1080 b can be added to the sample of nearby benchmark planets accessible for detailed study with JWST.