Xi Cygni

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Xi Cygni
XiCygni JeffJohnson.jpg
Xi Cygni (center star) at edge of NGC 7000.
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus
Right ascension 21h 04m 55.86s[1]
Declination +43° 55′ 40.3″[1]
Apparent magnitude (V) 3.73[2]
Characteristics
Spectral type K4:Ib- + A1.5V[3]
U−B color index +1.78[2]
B−V color index +1.66[2]
Astrometry
Radial velocity (Rv) -19.10[4] km/s
Proper motion (μ) RA: +7.97[1] mas/yr
Dec.: +0.06[1] mas/yr
Parallax (π) 3.87 ± 0.16[1] mas
Distance 361[3] pc
Absolute magnitude (MV) −4.3/+1.3[3]
Orbit[5]
Period (P) 6,750 ± 200 days
Semi-major axis (a) ~766 R
Eccentricity (e) 0.25 ± 0.07
Inclination (i) ~50°
Details
Primary
Mass ~8[5] M
Luminosity 5,303[6] L
Surface gravity (log g) 1.00[7] cgs
Temperature 3,920[7] K
Metallicity [Fe/H] −0.41[7] dex
Other designations
62 Cygni, FK5 792, GC 29459, HIP 104060, HR 8079, HD 200905, SAO 50424
Database references
SIMBAD data

Xi Cygni is a spectroscopic binary star in the constellation Hydra. Its apparent magnitude is 3.73. Located around 258 parsecs (840 ly) distant, the primary is a supergiant or bright giant of spectral type K4.5, while the secondary is a A-type main-sequence star of spectral type A2.

References[edit]

  1. ^ a b c d e van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. 
  2. ^ a b c Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237: 0. Bibcode:2002yCat.2237....0D. 
  3. ^ a b c Ginestet, N.; Carquillat, J. M. (2002). "Spectral Classification of the Hot Components of a Large Sample of Stars with Composite Spectra, and Implication for the Absolute Magnitudes of the Cool Supergiant Components". The Astrophysical Journal Supplement Series 143 (2): 513. Bibcode:2002ApJS..143..513G. doi:10.1086/342942. 
  4. ^ Famaey, B.; et al. (January 2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters", Astronomy and Astrophysics 430 (1): 165–186, arXiv:astro-ph/0409579, Bibcode:2005A&A...430..165F, doi:10.1051/0004-6361:20041272 
  5. ^ a b Reimers, D.; Schroeder, K.-P. (1989). "Observations of modulation and phase displacement of the stellar wind in six red giant spectroscopic binaries". Astronomy and Astrophysics 214: 261. Bibcode:1989A&A...214..261R. 
  6. ^ McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental parameters and infrared excesses of Hipparcos stars". Monthly Notices of the Royal Astronomical Society 427: 343. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. 
  7. ^ a b c Hekker, S.; Meléndez, J. (2007). "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters". Astronomy and Astrophysics 475 (3): 1003. arXiv:0709.1145. Bibcode:2007A&A...475.1003H. doi:10.1051/0004-6361:20078233.