TOI-1080 b: a temperate, rocky planet orbiting a quiet M4V host
Abstract We present the detection and validation of a small, temperate transiting exoplanet orbiting TOI-1080 every 3.9652482$_{-0.0000015}^{+0.0000014}$ days. The host is a quiet M4V star at 25.6 pc. The planet signal was first detected by TESS and validated using TESS and ground-based observations. By fitting the available light curves, the planet radius is measured to be 1.200 ± 0.058R⊕ and its equilibrium temperature of $368_{-10.}^{+12}$ K. With NIRPS radial velocities, we are able to place a 3-σ upper limit on the mass of TOI-1080 b of 10.7 M⊕.Our injection-recovery tests enable us to discard additional transiting planets in the TOI-1080 system with radii down to 0.9 R⊕ and periods between 0.5 and 7.7 days, and planets with radii larger than 1.4 R⊕ for periods up to 19 days. We demonstrate that it is highly amenable to characterisation 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.
Authors
- Léna Parc (ORCID: https://orcid.org/0000-0002-7382-1913)
- Sebastián Zúñiga-Fernández (ORCID: https://orcid.org/0000-0002-9350-830X)
- Abderahmane Soubkiou (ORCID: https://orcid.org/0000-0002-0345-2147)
- Mathilde Timmermans (ORCID: https://orcid.org/0009-0008-2214-5039)
- Urs Schroffenegger
- I. Plauchu–Frayn (ORCID: https://orcid.org/0000-0002-4166-6349)
- Elsa Ducrot
- Edgardo Jofré
- Carl Ziegler
- Xavier Bonfils
- Zouhair Benkhaldoun
- F Davoudi
- K G Stassun
- A Segura
- S Páez
- F J Pozuelos
- A H M J Triaud
- Y Gómez Maqueo Chew
- B V Rackham
- J I González-Hernández
- F Bouchy
- R Schwarz
- M Pichardo Marcano
- R Doyon
- J M Jenkins
- M J Hooton
- M G Scott
- G Dransfield
- C Cadieux
- K Barkaoui
- B O Demory
- J R De Medeiros
- E Jehin
- A Khandelwal
- N C Santos
- K A Collins
- J M Almenara
- A J Burgasser
- T G Tan
- M Gachaoui
- M Gillon
- S Yalç℩nkaya
- R Petrucci
- F Zong Lang
Institutions
- University of Geneva (CH)
- University of Bern (CH)
- Cadi Ayyad University (MA)
- Ames Research Center (US)
- Centre National de la Recherche Scientifique (FR)
- Planetary Science Institute (US)
- Ankara University (TR)
- Consejo Nacional de Investigaciones Científicas y Técnicas (AR)
- University of Liège (BE)
- Universidad de La Laguna (ES)
- Universidad Autónoma de la Ciudad de México (MX)
- Universidade do Porto (PT)
- Vanderbilt University (US)
- Stephen F. Austin State University (US)
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR)
- Université Paris-Saclay (FR)
- Northeast Catholic College (US)
- Universidade Federal do Rio Grande do Norte (BR)
- University of California San Diego (US)
- University of Oxford (GB)
- Astrophysique, Instrumentation et Modélisation (FR)
- Institute of Astrophysics and Space Sciences (PT)
- Perth Exoplanet Survey Telescope Observatory (AU)
- Argentine National Observatory (AR)
- Center for Astrophysics Harvard & Smithsonian (US)
- CEA Paris-Saclay (FR)
- Instituto de Astrofísica de Canarias (ES)
- Astronomy and Space (AU)
- Montreal Clinical Research Institute (CA)
- Instituto de Astrofísica de Andalucía (ES)
- Massachusetts Institute of Technology (US)
- University of Birmingham (GB)
- Universidad Nacional Autónoma de México (MX)
- Université Grenoble Alpes (FR)
Publication Details
- Journal
- Monthly Notices of the Royal Astronomical Society
- Published
- 2026-03-04
- DOI
- https://doi.org/10.1093/mnras/stag438
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00