U Orionis

U Orionis
Location of U Orionis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Orion
Right ascension 05h 55m 49.17076s[1]
Declination +20° 10′ 30.6779″[1]
Apparent magnitude (V) 4.8 - 13.0[2]
Characteristics
Spectral type M6e-M9.5e[2]
B−V color index +2.07[3]
Variable type Mira[2]
Astrometry
Parallax (π)3.4924 ± 0.1820 mas[1]
Distance930 ± 50 ly
(290 ± 10 pc)
Details
Mass0.88[4] M☉
Radius370±96[5] R☉
Luminosity7,000[6] L☉
Surface gravity (log g)−0.44[4] cgs
Temperature2,641[4] K
Metallicity [Fe/H]0.54[4] dex
Other designations
U Ori, BD+20°1171a, HD 39816, HIP 28041, HR 2063, SAO 77730[7]
Database references
SIMBADdata

U Orionis (abbreviated U Ori) is a Mira-type variable star in the constellation Orion. It is a classical long period variable star that has been well observed for over 120 years.

  1. ^ a b c Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  2. ^ a b c Samus', N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
  3. ^ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
  4. ^ a b c d Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevic, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; de Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (1 August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy and Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. ISSN 0004-6361. S2CID 131780028.
  5. ^ Van Belle; et al. (1996). "Angular Size Measurements of 18 Mira Variable Stars at 2.2 microns". Astronomical Journal. 112: 2147. Bibcode:1996AJ....112.2147V. doi:10.1086/118170.
  6. ^ Mondal & Chandrasekhar (2004). "Evidence of asymmetry in Mira variable U Ori". Monthly Notices of the Royal Astronomical Society. 348 (4): 1332–1336. Bibcode:2004MNRAS.348.1332M. doi:10.1111/j.1365-2966.2004.07454.x.
  7. ^ "V* U Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 25 January 2018.