G 9-40 b

Last updated
G 9-40 b
Discovery [1]
Discovery dateDecember 2019
radial velocity and transit
Designations
K2-313 b [2]
Orbital characteristics [3]
0.04180±0.00064  AU
Eccentricity 0
5.7459982(20)  d
Inclination 89.03°±0.10°
Physical characteristics [3]
Mean radius
1.900±0.065  R🜨
Mass 4.00±0.63  M🜨
Mean density
3.20+0.63
−0.58
  g/cm3
10.8±1.8  m/s2
Temperature 440.6±7.6  K (167.5 °C; 333.4 °F, equilibrium)

    G 9-40 b is a sub-Neptune exoplanet that has an orbital period of 5.7 days. The host star is a red dwarf located 91 light-years (28 parsecs ) away from Earth in the constellation Cancer. [4] The planet was discovered in 2019. [5] [6] The planet's density is too low for a rocky composition, suggesting that it is either water-rich or has a significant hydrogen atmosphere. [3]

    See also

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    References

    1. Stefánsson, Guðmundur; et al. (2019), "A sub-Neptune sized planet transiting the M2.5-dwarf G 9-40: Validation with the Habitable-zone Planet Finder", The Astronomical Journal, 159 (3): 100, arXiv: 1912.00291 , Bibcode:2020AJ....159..100S, doi: 10.3847/1538-3881/ab5f15 , S2CID   208526899
    2. "G 9-40 b Overview". NASA Exoplanet Archive . Retrieved 15 June 2024.
    3. 1 2 3 Luque, R.; et al. (2022), "Precise mass determination for the keystone sub-Neptune planet transiting the mid-type M dwarf G 9-40", Astronomy & Astrophysics, 666: A154, arXiv: 2208.07287 , Bibcode:2022A&A...666A.154L, doi:10.1051/0004-6361/202244426, S2CID   251564548
    4. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211 . Bibcode:2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940 . S2CID   244398875. Gaia DR3 record for this source at VizieR.
    5. "Exoplanet-catalog". Exoplanet Exploration: Planets Beyond our Solar System. Retrieved 2021-03-23.
    6. "The Extrasolar Planet Encyclopaedia — G 9-40 b". Extrasolar Planets Encyclopaedia . Retrieved 28 March 2021.