Astronomy:LTT 9779 b
| Discovery | |
|---|---|
| Discovery date | 2020 |
| Transit | |
| Designations | |
| Cuancoá | |
| Orbital characteristics | |
| 0.01679 AU | |
| Eccentricity | <0.01 |
| Inclination | 76.39 ± 0.43° |
| Star | LTT 9779 |
| Physical characteristics | |
| Mean radius | 4.72 ± 0.23 R🜨 |
| Mass | 29.32 M🜨 |
| Albedo | 0.8 |
| Physics | 2,305 K (2,032 °C; 3,689 °F) (Dayside) |
LTT 9779 b, officially named Cuancoá, is a Neptune-sized planet orbiting the sunlike star LTT 9779, or Uúba. As of 2023, it has the highest-known albedo of any planet.[1]
Characteristics
LTT 9779 b is one of the few known planets in the Neptunian desert.[2] It is highly reflective, with an albedo of 0.8.[3] This makes it the most reflective exoplanet discovered so far. It completes an orbit around LTT 9779 in less than a day, making temperatures on the day side soar to over 2,000 degrees Celsius.[4] Global climate models of the planet indicate it has a very metal-rich atmosphere, with clouds made of silicate likely being present.[1]
Being in the Neptunian desert, LTT 9779 b is a very rare class of planet, with few like it being known. It is estimated that only 1 in 200 Sun-like stars possess a planet with an orbital period of less than a day,[2] and most of those are Hot Jupiters or rocky planets, with ultra-hot Neptune planets being rare.[2] Because of this, LTT 9779 b has been extensively studied by many space telescopes including Hubble and James Webb.
Name
LTT 9779 b was officially named Cuancoá in 2022 by the International Astronomical Union, as part of the NameExoWorlds competition. Cuancoá is a word that refers to the morning star in the U'wa language.[5] Cuancoá's star was named Uúba after the word for "stars", "seeds", and "eyes", in the same language.
See also
- NGTS-4b, another planet in the Neptunian desert
References
- ↑ 1.0 1.1 Hoyer, S.; Jenkins, J. S.; Parmentier, V.; Deleuil, M.; Scandariato, G.; Wilson, T. G.; Díaz, M. R.; Crossfield, I. J. M. et al. (2023-07-01). "The extremely high albedo of LTT 9779 b revealed by CHEOPS - An ultrahot Neptune with a highly metallic atmosphere" (in en). Astronomy & Astrophysics 675: A81. doi:10.1051/0004-6361/202346117. ISSN 0004-6361. https://www.aanda.org/articles/aa/abs/2023/07/aa46117-23/aa46117-23.html.
- ↑ 2.0 2.1 2.2 Jenkins, James S.; Díaz, Matías R.; Kurtovic, Nicolás T.; Espinoza, Néstor; Vines, Jose I.; Rojas, Pablo A. Peña; Brahm, Rafael; Torres, Pascal et al. (2020-09-14). "An Ultra-Hot Neptune in the Neptune desert". Nature Astronomy 4 (12): 1148–1157. doi:10.1038/s41550-020-1142-z. ISSN 2397-3366.
- ↑ "Cheops shows scorching exoplanet acts like a mirror" (in en). https://www.esa.int/Science_Exploration/Space_Science/Cheops/Cheops_shows_scorching_exoplanet_acts_like_a_mirror.
- ↑ Crossfield, Ian J. M.; Dragomir, Diana; Cowan, Nicolas B.; Daylan, Tansu; Wong, Ian; Kataria, Tiffany; Deming, Drake; Kreidberg, Laura et al. (2020-10-26). "Phase Curves of Hot Neptune LTT 9779b Suggest a High-Metallicity Atmosphere". The Astrophysical Journal 903 (1): L7. doi:10.3847/2041-8213/abbc71. ISSN 2041-8213.
- ↑ "2022 Approved Names" (in en). https://www.nameexoworlds.iau.org/2022approved-names.
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