Xi Tauri

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ξ Tauri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Taurus
Right ascension 03h 27m 10.151s[1]
Declination +09° 43′ 57.63″[1]
Apparent magnitude (V) 3.73
Characteristics
Spectral type B8Vn + B8Vn + B7Vn + F
Astrometry
Proper motion (μ) RA: 50.58 ± 1.48[1] mas/yr
Dec.: –39.54 ± 1.40[1] mas/yr
Parallax (π) 15.60 ± 1.04[1] mas
Distance 210 ± 10 ly
(64 ± 4 pc)
Orbit[2]
Primary ξ Tau Aa
Companion ξ Tau Ab
Period (P) 7.146651 ± 0.000010 d
Eccentricity (e) 0.0 ± 0.05
Inclination (i) 86.2 ± 0.5°
Longitude of the node (Ω) 350.5 ± 4.0°
Periastron epoch (T) JD 2448299.075 ± 0.010
Argument of periastron (ω)
(secondary)
90 ± 10°
Semi-amplitude (K1)
(primary)
89.1 ± 10.0 km/s
Orbit[2]
Primary ξ Tau Aa-Ab
Companion ξ Tau B
Period (P) 145.12 ± 0.055 d
Semi-major axis (a) 16.09 ± 0.18 mas
Eccentricity (e) 0.213 ± 0.007
Inclination (i) 87.07 ± 0.19°
Longitude of the node (Ω) 328.63 ± 0.38°
Periastron epoch (T) JD 2453712.90 ± 0.34
Argument of periastron (ω)
(secondary)
163.07 ± 0.13°
Semi-amplitude (K1)
(primary)
38.02 ± 5.0 km/s
Details[2]
ξ Tau Aa
Mass 2.29 ± 0.91 M
Radius 2.0 ± 0.2 R
Surface gravity (log g) 4.2 cgs
Temperature 9400 ± 500 K
Rotational velocity (v sin i) 33 ± 2 km/s
ξ Tau Ab
Mass 2.20 ± 0.78 M
Radius 1.5 ± 0.2 R
Surface gravity (log g) 4.2 cgs
Temperature 9200 ± 500 K
Rotational velocity (v sin i) 34 ± 2 km/s
ξ Tau B
Mass 3.08 ± 1.24 M
Surface gravity (log g) 4.3 ± 0.1 cgs
Temperature 15100 ± 200 K
Rotational velocity (v sin i) 246 ± 10 km/s
Other designations
2 Tau, HR 1038, HD 21364, BD+09° 439, HIP 16083, SAO 111195[3]
Database references
SIMBAD data

Xi Tauri (ξ Tau, ξ Tauri) is a hierarchical quadruple system[2] in the constellation Taurus.

Xi Tauri is a spectroscopic and eclipsing quadruple star. It consists of three blue-white B-type main sequence dwarfs. Two of the stars form an eclipsing binary system and revolve around each other once every 7.15 days. These in turn orbit the third star once every 145 days. The fourth star is a F star that orbits the other three stars in a roughly fifty-year period.[4] The mean combined apparent magnitude of the system is +3.73, but because the stars eclipse one another during their orbits, it is classified as a variable star, and its brightness varies from magnitude +3.70 to +3.79. Xi Tauri is approximately 210 light years from Earth.[1]

References[edit]

  1. ^ a b c d e f van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. Bibcode:2007A&A...474..653V. arXiv:0708.1752Freely accessible. doi:10.1051/0004-6361:20078357. Vizier catalog entry
  2. ^ a b c d Nemravová, J. A.; et al. (2013). "An Unusual Quadruple System ξ Tauri". Central European Astrophysical Bulletin. 37 (1): 207–216. Bibcode:2013CEAB...37..207N. 
  3. ^ "ksi Tau -- Star". SIMBAD Astronomical Database. Centre de données astronomiques de Strasbourg. Retrieved 2013-09-29. 
  4. ^ Rica Romero, F. M. (2010). "Orbital elements for eight binaries. Study of the nature of wide components. I" (PDF). Revista Mexicana de Astronomía y Astrofísica. 46: 263–277. Bibcode:2010RMxAA..46..263R.