Upsilon2 Cassiopeiae

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υ2 Cassiopeiae
Upsilon2 cassiopeiae diagram.jpg
Map of the Bayer-designated stars in Cassiopeia. Upsilon2 Cassiopeiae is circled.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cassiopeia
Right ascension 00h 56m 39.905s[1]
Declination +59° 10′ 51.80″[1]
Apparent magnitude (V) +4.62[2]
Spectral type G8 IIIb Fe-0.5[3]
U−B color index +0.68[2]
B−V color index +0.96[2]
Variable type none
Radial velocity (Rv) −47.73±0.12[4] km/s
Proper motion (μ) RA: −92.65±0.18[1] mas/yr
Dec.: −45.50±0.16[1] mas/yr
Parallax (π) 16.32 ± 0.23[1] mas
Distance 200 ± 3 ly
(61.3 ± 0.9 pc)
Absolute magnitude (MV) +0.62[5]
Mass 1.44±0.16 M
Radius 10.37±0.26 R
Luminosity 67.6 L
Surface gravity (log g) 2.75±0.19 cgs
Temperature 4,937±14 K
Metallicity [Fe/H] −0.35±0.03 dex
Rotational velocity (v sin i) 0.54±0.38 km/s
Age 2.20±0.62 Gyr
Other designations
υ2 Cas, 28 Cas, BD+58° 138, HD 5395, HIP 4422, HR 265, SAO 21855
Database references

Upsilon2 Cassiopeiae2 Cassiopeiae) is a star in the constellation Cassiopeia. υ2 Cassiopeiae is a yellow G-type giant with an apparent magnitude of +4.62. It is approximately 200 light years from Earth.[1] This is a barium star, which may indicate it has an orbiting white dwarf companion.[5]


  1. ^ a b c d e f van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752Freely accessible. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. Vizier catalog entry
  2. ^ a b c Argue, A. N. (1966), "UBV photometry of 550 F, G and K type stars", Monthly Notices of the Royal Astronomical Society, 133: 475, Bibcode:1966MNRAS.133..475A, doi:10.1093/mnras/133.4.475. 
  3. ^ Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373. 
  4. ^ a b Jofré, E.; et al. (2015), "Stellar parameters and chemical abundances of 223 evolved stars with and without planets", Astronomy & Astrophysics, 574: A50, arXiv:1410.6422Freely accessible, Bibcode:2015A&A...574A..50J, doi:10.1051/0004-6361/201424474. 
  5. ^ a b Bergeat, J.; Knapik, A. (May 1997), "The barium stars in the Hertzsprung-Russel diagram.", Astronomy and Astrophysics, 321: L9, Bibcode:1997A&A...321L...9B.