TOI-2136 b
| Discovery[1] | |
|---|---|
| Discovered by | Tianjun Gan et al. (2022) |
| Discovery site | TESS |
| Discovery date | 2022 |
| Radial velocity | |
| Orbital characteristics | |
| Star | TOI-2136 |
| Physical characteristics[1] | |
| 2.19±0.17 | |
| Mass | 6.37+2.45 −2.29 |
TOI-2136 b is a sub-Neptune exoplanet orbiting the nearby red dwarf star TOI-2136.[1] It was discovered in 2022 through transit observations by NASA's TESS and independently validated using ground-based photometry and radial velocity measurements.[1][2] The planet has an orbital period of approximately 7.85 days and lies at a distance of about 108 light-years from Earth.[3][4] TOI-2136 b is known for its position near the red dwarf for planets predicted by atmospheric mass-loss models and for its potential as a hycean world.[1][2]
Discovery
[edit]TOI-2136 b was first identified as the candidate TOI-2136.01 from photometric data collected during TESS's primary mission.[1] The transit signal was detected with an orbital period of 7.85 days around the red dwarf star TOI-2136.[1]
Independent confirmation came from Gan et al. (2022) who used ground-based multi-wavelength photometry, high-angular-resolution imaging, and precise radial-velocity measurements from the CFHT/SPIRou instrument to validate the planet and measure its mass.[1] Kawauchi et al. (2022) validated it using TESS data, ground-based photometry, and radial velocities from the Subaru Telescope's IRD instrument, while also conducting a search for helium in its atmosphere[2] and Beard et al. (2022) provided additional validation using the Habitable-Zone Planet Finder (HPF) on the Hobby-Eberly Telescope, placing an upper mass limit.[5]
Characteristics
[edit]The mass–radius combination of TOI-2136 b is compatible with a wide range of interior compositions, from water or ice dominated worlds to gas-enveloped rocky cores.[1] Interior structure models suggest it may retain a small H/He envelope (mass fraction ~1–2%) atop a rocky or icy core. It lies relatively close to the red dwarfs, where thermally driven atmospheric escape is expected to sculpt planetary populations.[1]
TOI-2136 b has also been discussed as a potential Cold Haber World, where microbial life could produce detectable ammonia via a process similar to the Haber process under high-pressure ocean conditions and could be a future target for JWST.[6]
See also
[edit]References
[edit]- 1 2 3 4 5 6 7 8 9 10 Gan, Tianjun (2022). "TESS discovery of a sub-Neptune around the mid-M dwarf TOI-2136". Monthly Notices of the Royal Astronomical Society. 514 (3): 4120–4132. doi:10.1093/mnras/stac1554.
- 1 2 3 Kawauchi, K.; Murgas, F.; Palle, E.; Narita, N.; Fukui, A.; Hirano, T.; Parviainen, H.; Ishikawa, H. T.; Watanabe, N.; Esparaza-Borges, E.; Kuzuhara, M.; Orell-Miquel, J.; Krishnamurthy, V.; Mori, M.; Kagetani, T. (2022-10-01). "Validation and atmospheric exploration of the sub-Neptune TOI-2136b around a nearby M3 dwarf". Astronomy & Astrophysics. 666: A4. Bibcode:2022A&A...666A...4K. doi:10.1051/0004-6361/202243381. ISSN 0004-6361.
- ↑ "TOI-2136 | NASA Exoplanet Archive". exoplanetarchive.ipac.caltech.edu. Retrieved 2026-04-09.
- ↑ Soubkiou, A.; Barkaoui, K.; Gan, T.; Benkhaldoun, Z. (2024). "Discovery of Three Sub-Neptune Exoplanets Orbiting M Dwarfs with TESS". Proceedings of the International Astronomical Union. 20 (S393): 187–195. doi:10.1017/S174392132400262X. ISSN 1743-9213.
- ↑ Beard, Corey; Robertson, Paul; Kanodia, Shubham; Libby-Roberts, Jessica; Cañas, Caleb I.; Gupta, Arvind F.; Holcomb, Rae; Jones, Sinclaire; Kobulnicky, Henry A.; Lin, Andrea S. J.; Lubin, Jack; Maney, Marissa; Parker, Brock A.; Stefánsson, Guðmundur; Cochran, William D. (2022-06-01). "TOI-1696 and TOI-2136: Constraining the Masses of Two Mini-Neptunes with the Habitable-Zone Planet Finder". The Astronomical Journal. 163 (6): 286. arXiv:2204.09063. Bibcode:2022AJ....163..286B. doi:10.3847/1538-3881/ac69ec. ISSN 0004-6256.
- ↑ Robertson, Paul M. (2022-09-15). "TOI-2136b: Habitable, but not to us?". The Habitable Zone Planet Finder. Retrieved 2026-04-09.