TOI-7166 b: a habitable zone mini-Neptune planet around a nearby low-mass star

Journal article

We present the discovery and validation of TOI-7166 b, a planet orbiting a nearby low-mass star. We validated the planet by combining Transiting Exoplanet Survey Satellite and multicolour high-precision photometric observations from ground-based telescopes, together with spectroscopic data, high-contrast imaging, archival images, and statistical arguments. The host star is an M4-type dwarf at a distance of 35 pc from the Sun. It has a mass and a radius of and , respectively. TOI-7166 b has an orbital period of 12.9 d, which places it close to the inner edge of the Habitable Zone of its host star, receiving an insolation flux of and an equilibrium temperature of K (assuming a null Bond albedo). The brightness of the host star makes TOI-7166 a suitable target for radial velocity follow-up to measure the planetary mass and bulk density. Moreover, the physical parameters of the system including the infrared brightness () of the star and the planet-to-star radius ratio () make TOI-7166 b an exquisite target for transmission spectroscopic observations with the James Webb Space Telescope, to constrain the exoplanet atmospheric compositions.

Authors: Barkaoui, K; Pozuelos, FJ; Rackham, BV; Burgasser, AJ; Triaud, AHMJ

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Oxford University Press
• Journal: Monthly Notices of the Royal Astronomical Society
• Volume: 544
• Issue: 2
• Pages: 2637-2652
• Publication date: 2025-10-21
• Acceptance date: 2025-10-11
• DOI: 10.1093/mnras/staf1807
• EISSN: 1365-2966
• ISSN: 0035-8711
• Language: English
• Keywords: exoplanets; stars: low-mass; stars: late-type; stars: individual; planets and satellites: detection