Gliese 433
Gliese 433 is a dim red dwarf star in the constellation of Hydra, roughly 29.5 light years away from the Sun. Astronomers have announced the discovery of a super-Earth extrasolar planet in close orbit.
Planetary system
Gliese 433 b is an extrasolar planet which orbits the star Gliese 433. This planet is a super-Earth with at least six times the mass of Earth and takes approximately seven days to orbit the star at a semimajor axis of approximately 0.056 AU. The planet was announced in a press release in October 2009, but no discovery paper at the time was made available.[5] A study described in a 2014 paper by Tuomi et al. confirmed both Gliese 433 b and another candidate planet, previously detected in 2012, Gliese 433 c.[6]
Gliese 433 d, whose discovery was published in January 2020, is very similar in mass to Gliese 433 b but orbits slightly further out, actually within the optimistic habitable zone of the star, but it is still too close to the star, and therefore too warm, to be inside the narrower boundaries of the conservative habitable zone.[2][7]
Gliese 433 c orbits the furthest out from the star. To date it is the nearest, widest orbiting, and coldest Neptune-like planet yet detected. It is also notable in having an unusually eccentric orbit for a large planet so far from its parent single star and other planets.[7]
_Gliese_433_Star_system.png.webp)
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >6.0 M⊕ | 0.054 | 7.0 | 0.08 | — | — |
| Gliese 433 d | 5.223 ± 0.921 M⊕ | 0.178 ± 0.006 | 36.059 ± 0.016 | 0.07 ± 0.05 | — | — |
| c | ≥28.78+19.15 −10.46 M⊕ |
4.692+1.169 −0.768 |
4,873.923+1,796.128 −1,034.762 |
0.21+0.08 −0.21 |
— | — |
References
- Zechmeister, M.; Kürster, M.; Endl, M. (August 6, 2009). "The M dwarf planet search programme at the ESO VLT + UVES. A search for terrestrial planets in the habitable zone of M dwarfs". Astronomy and Astrophysics. 505 (2): 859–871. arXiv:0908.0944. Bibcode:2009A&A...505..859Z. doi:10.1051/0004-6361/200912479. S2CID 16845441.
- "PHL's Exoplanets Catalog". University of Puerto Rico at Arecibo. 5 December 2019. Retrieved 26 January 2020.
- Lindgren, Sara; Heiter, Ulrike (2017). "Metallicity determination of M dwarfs. Expanded parameter range in metallicity and effective temperature". Astronomy and Astrophysics. 604: A97. arXiv:1705.08785. Bibcode:2017A&A...604A..97L. doi:10.1051/0004-6361/201730715. S2CID 119216828.
- Suárez Mascareño, A.; et al. (September 2015), "Rotation periods of late-type dwarf stars from time series high-resolution spectroscopy of chromospheric indicators", Monthly Notices of the Royal Astronomical Society, 452 (3): 2745–2756, arXiv:1506.08039, Bibcode:2015MNRAS.452.2745S, doi:10.1093/mnras/stv1441, S2CID 119181646.
- "32 New Exoplanets Found". ESO News. ESO. Retrieved 15 February 2012.
- Tuomi, Mikko; Jones, Hugh R. A.; Barnes, John R.; et al. (2014). "Bayesian search for low-mass planets around nearby M dwarfs – estimates for occurrence rate based on global detectability statistics". Monthly Notices of the Royal Astronomical Society. 441 (2): 1545–1569. arXiv:1403.0430. Bibcode:2014MNRAS.441.1545T. doi:10.1093/mnras/stu358. ISSN 1365-2966.
- Feng, Fabo; Butler, R. Paul; Shectman, Stephen A.; et al. (2020). "Search for Nearby Earth Analogs. II. Detection of Five New Planets, Eight Planet Candidates, and Confirmation of Three Planets around Nine Nearby M Dwarfs". The Astrophysical Journal Supplement Series. 246 (1): 38. arXiv:2001.02577. Bibcode:2020ApJS..246...11F. doi:10.3847/1538-4365/ab5e7c. ISSN 1538-4365. S2CID 210064560. 11.