Tau2 Capricorni

From Wikipedia, the free encyclopedia
  (Redirected from 14 Capricorni)
Jump to navigation Jump to search
Tau2 Capricorni
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Capricornus
Right ascension  20h 39m 16.31779s[1]
Declination +14° 57′ 17.1352″[1]
Apparent magnitude (V) 5.20 (5.77 + 9.5 + 6.19)[2]
Spectral type B6III + ? + B6IV[2]
Proper motion (μ) RA: +2.62[1] mas/yr
Dec.: −19.46[1] mas/yr
Parallax (π) 2.87 ± 0.65[1] mas
Distance approx. 1,100 ly
(approx. 350 pc)
Primary τ2 Cap A
Companion τ2 Cap B
Period (P) 420 yr
Semi-major axis (a) 0.48″
Eccentricity (e) 0.73
Inclination (i) 75°
Longitude of the node (Ω) 93.0°
Periastron epoch (T) 1915.0
Argument of periastron (ω)
Other designations
τ2 Cap, 14 Cap, BD−15° 5743, GC 28748, HD 196662, HIP 101923, HR 7889, SAO 163771, ADS 14099, CCDM J20392-1457[4]
Database references

Tau2 Capricorni2 Capricorni) is a triple star[2] system in the constellation Capricornus. It is approximately 1,100 light years from Earth. The system has a combined apparent magnitude of +5.20.[2] Because it is near the ecliptic, τ2 Capricorni can be occulted by the Moon, and also (rarely) by planets.

The primary component, τ2 Capricorni A, is a blue-white B-type giant with an apparent magnitude of +5.8. At a distance of only 0.34 arcseconds is the second component, τ2 Capricorni B, a blue-white B-type subgiant with an apparent magnitude of +6.3. These two stars orbit around their common centre of mass once every 420 years.[3] A possible third component with an apparent magnitude of +9.5,[2] detected by studying the star during occultation, is located 0.052 arcseconds away from the A component.


  1. ^ a b c d e van Leeuwen, F. (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 d e Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x.
  3. ^ a b Hartkopf, W. I.; et al. (June 30, 2006), Sixth Catalog of Orbits of Visual Binary Stars, United States Naval Observatory, retrieved 2017-06-02.
  4. ^ "tau Cap". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-08-30.