L 98-59 b
![]() Artist's impression and size comparison with Earth and Mars | |
Discovery | |
---|---|
Discovery date | 2018[1] |
Transit[1] | |
Orbital characteristics | |
0.0227 AU[1] | |
Eccentricity | 0.09[1] |
2.2532 d[1] | |
Star | L 98-59 |
Physical characteristics | |
0.85 R🜨[2] | |
Mass | 0.40 ME[2] |
Temperature | 603 K (330°C)[3] |
![](http://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/L98-59b.png/220px-L98-59b.png)
L 98-59 b is an exoplanet having a size between that of the Earth and Mars and a mass only half that of Venus.[2] It orbits L 98-59, a red dwarf 35 light-years away in the constellation Volans. There are at least 3 (possibly 4) other planets in the system: L 98-59 c, d, e, and the unconfirmed L 98-59 f.[2] Its discovery was announced on 27 June 2019 on the NASA website. It was the smallest planet discovered by TESS[4] until the discovery of LHS 1678b,[5] and was the lowest-mass planet whose mass has been measured using radial velocities[2] until Proxima Centauri d was found in 2022.[6]
Characteristics
[edit]L 98-59 b orbits in 2.25 days and stays so close to the star that it receives 22 times more energy than Earth receives from the Sun. There are 4 confirmed planets in the system but they are not in the habitable zone of the host star.[4] The temperature of the planet detected by TESS is 330 °C.[3] In 2022, transmission spectroscopy has indicated that the planet has either no atmosphere or opaque atmosphere with the high-altitude hazes.[7]
References
[edit]- ^ a b c d e "The Extrasolar Planet Encyclopaedia-L 98-59 b". Extrasolar Planets Encyclopaedia. 1995.
- ^ a b c d e Demangeon, Oliver D. S.; Zapatero Osorio, M. R.; Alibert, Y.; Barros, S. C. C.; Adibekyan, V.; Tabernero, H. M.; et al. (July 2021). "A warm terrestrial planet with half the mass of Venus transiting a nearby star" (PDF). Astronomy & Astrophysics. 653: 38. arXiv:2108.03323. Bibcode:2021A&A...653A..41D. doi:10.1051/0004-6361/202140728. S2CID 236957385.
- ^ a b "Canicule ? Il fait 330 degrés sur la petite exoplanète découverte par le télescope spatial TESS". Numerama (in French). 2019-07-01. Retrieved 2019-07-30.
- ^ a b Garner, Rob (2019-06-24). "NASA's TESS Mission Finds Its Smallest Planet Yet". NASA. Retrieved 2019-06-29.
- ^ Silverstein, Michele L.; Schlieder, Joshua E.; Barclay, Thomas; Hord, Benjamin J.; Jao, Wei-Chun; Vrijmoet, Eliot Halley; Henry, Todd J.; Cloutier, Ryan; Kostov, Veselin B.; Kruse, Ethan; Winters, Jennifer G.; Irwin, Jonathan M.; Kane, Stephen R.; Stassun, Keivan G.; Huang, Chelsea (2022-04-01). "The LHS 1678 System: Two Earth-Sized Transiting Planets and an Astrometric Companion Orbiting an M Dwarf Near the Convective Boundary at 20 pc". The Astronomical Journal. 163 (4): 151. arXiv:2110.12079. Bibcode:2022AJ....163..151S. doi:10.3847/1538-3881/ac32e3. ISSN 0004-6256. S2CID 239768873.
- ^ Faria, J. P.; Suárez Mascareño, A.; et al. (January 4, 2022). "A candidate short-period sub-Earth orbiting Proxima Centauri" (PDF). Astronomy & Astrophysics. 658. European Southern Observatory: 17. arXiv:2202.05188. Bibcode:2022A&A...658A.115F. doi:10.1051/0004-6361/202142337.
- ^ Damiano, Mario; Hu, Renyu; Barclay, Thomas; Zieba, Sebastian; Kreidberg, Laura; Brande, Jonathan; Colon, Knicole D.; Covone, Giovanni; Crossfield, Ian; Domagal-Goldman, Shawn D.; Fauchez, Thomas J.; Fiscale, Stefano; Gallo, Francesco; Gilbert, Emily; Hedges, Christina L.; Kite, Edwin S.; Kopparapu, Ravi K.; Kostov, Veselin B.; Morley, Caroline; Mullally, Susan E.; Pidhorodetska, Daria; Schlieder, Joshua E.; Quintana, Elisa V. (2022), "A Transmission Spectrum of the Sub-Earth Planet L98-59 b in 1.1–1.7 μm", The Astronomical Journal, 164 (5): 225, arXiv:2210.10008, Bibcode:2022AJ....164..225D, doi:10.3847/1538-3881/ac9472, S2CID 252968265