HD 155233 b

Last updated
HD 155233 b
Discovery [1]
Discovered by Wittenmyer et al.
Discovery dateOctober 19, 2015
Radial velocity
Designations
HIP 84056 b
Orbital characteristics [2]
2.065+0.059
−0.062
  AU
Eccentricity 0.079+0.06
−0.053
825.8+9.9
−8.8
  d

2.261+0.027
−0.024
  yr
Inclination 5.2°±1.1° or 174.8°±1.1°
91°+21°
−17°
2,455,368+192
−92
  JD
157°+44°
−50°
Star HD 155233
Physical characteristics [2]
Mass 31.9+8.5
−5.3
  MJ

    HD 155233 b is a confirmed brown dwarf orbiting around the K-type giant star HD 155233 every 826 days, some 244 light-years away. [3] It has a minimum mass of almost 3 times that of Jupiter, and so was initially thought to be a gas giant exoplanet similar to Jupiter. However, in 2023 the inclination and true mass of HD 155233 b were determined via astrometry, showing it to be a brown dwarf about 32 times the mass of Jupiter in a nearly face-on orbit. [2] [4]

    HD 155233 b was discovered by Wittenmyer et al. in October 2015. [1] The orbit and mass were refined in 2016, [5] and again in 2023. [2]

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    References

    1. 1 2 Wittenmyer, R. A.; Butler, R. P.; Wang, L.; Bergmann, C.; Salter, G. S.; Tinney, C. G.; Johnson, J. A. (2015), "The Pan-Pacific Planet Search III: Five companions orbiting giant stars", Monthly Notices of the Royal Astronomical Society, 455 (2): 1398–1405, arXiv: 1510.04343 , doi:10.1093/mnras/stv2396
    2. 1 2 3 4 Xiao, Guang-Yao; Liu, Yu-Juan; et al. (May 2023). "The Masses of a Sample of Radial-Velocity Exoplanets with Astrometric Measurements". Research in Astronomy and Astrophysics . 23 (5): 055022. arXiv: 2303.12409 . Bibcode:2023RAA....23e5022X. doi:10.1088/1674-4527/accb7e.
    3. Vallenari, A.; et al. (Gaia Collaboration) (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics . arXiv: 2208.00211 . doi: 10.1051/0004-6361/202243940 . Gaia DR3 record for this source at VizieR.
    4. "HD 155233". NASA Exoplanet Archive . Retrieved 8 July 2023.
    5. Jones, M. I.; Jenkins, J. S.; Brahm, R.; Wittenmyer, R. A.; Olivares e., F.; Melo, C. H. F.; Rojo, P.; Jordán, A.; Drass, H.; Butler, R. P.; Wang, L. (2016), "Four new planets around giant stars and the mass-metallicity correlation of planet-hosting stars", Astronomy & Astrophysics, 590: A38, arXiv: 1603.03738 , Bibcode:2016A&A...590A..38J, doi:10.1051/0004-6361/201628067, S2CID   45730401