Xi Boötis

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Xi Boötis A/B
Diagram showing star positions and boundaries of the Boötes constellation and its surroundings
Cercle rouge 100%.svg

Location of ξ Boötis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 14h 51m 23.37993s[1]
Declination +19° 06′ 01.6994″[1]
Apparent magnitude (V) 4.70/6.97
Characteristics
Spectral type G8 Ve + K4 Ve
U−B color index 0.24/1.15
B−V color index 0.73/1.15
R−I color index 0.43 / 0.28
Variable type BY Draconis/None
Flare Star
Astrometry
Radial velocity (Rv) +3.0[2] km/s
Proper motion (μ) RA: 154.98[1] mas/yr
Dec.: -66.43[1] mas/yr
Parallax (π) 148.98 ± 0.48[1] mas
Distance 21.89 ± 0.07 ly
(6.71 ± 0.02 pc)
Absolute magnitude (MV) 5.54/7.81
Orbit[3]
Companion Xi Boötis B
Period (P) 151.505 ± 0.170 yr
Semi-major axis (a) 4.9044 ± 0.0027"
Eccentricity (e) 0.5117 ± 0.0006
Inclination (i) 140.037 ± 0.095°
Longitude of the node (Ω) 168.100 ± 0.164°
Periastron epoch (T) 1909.361 ± 0.024
Argument of periastron (ω)
(secondary)
23.917 ± 0.214°
Details
ξ Boo A
Mass 0.90 ± 0.04[4] M
Radius 0.83[5] R
Luminosity (visual, LV) 0.49 L
Temperature 5551 ± 20[4] K
Metallicity [Fe/H] –0.21 ± 0.08[4] dex
Rotation 6.2[5]
Age 200[6] Myr
ξ Boo B
Mass 0.66 ± 0.07[4] M
Radius 0.61[5] R
Luminosity (visual, LV) 0.061 L
Temperature 4350 ± 150[4] K
Rotation 11.5[5]
Other designations
37 Boötis, BD +19°2870, GCTP 3360.00, Gl 566, HD 131156, HIP 72659, HR 5544, SAO 101250.
Database references
SIMBAD data
ARICNS data
Data sources:
Hipparcos Catalogue,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.)

Xi Boötis (ξ Boo, ξ Boötis) is a binary star[4] system 22 light years away from Earth. It is the nearest visible star in the constellation Boötes.

The primary star in this system is a BY Draconis variable with an apparent magnitude that varies from +4.52 to +4.67 with a period just over 10 days long, and is classified as a yellow G-type main sequence dwarf. The AB binary can be resolved even through smaller telescopes. The binary system contains some of the closest young solar-type stars to the Sun, with a system age of about 200 million years old.[6]

The primary star (A) has been identified as a candidate for possessing a Kuiper-like belt,[7] based on infrared observations. The estimated minimum mass of this dust disk is 2.4 times the mass of the Earth's Moon. (Compare to the value of 8.2 lunar masses for the Kuiper belt.)[8]

References[edit]

  1. ^ a b c d e van Leeuwen, Floor (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, arXiv:0708.1752v1, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357  Note: see VizieR catalogue I/311.
  2. ^ Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick, Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, University of Toronto: International Astronomical Union, Bibcode:1967IAUS...30...57E 
  3. ^ Wielen, R. (November 1962), "Automatic orbit computation for visual binaries", Astronomical Journal 67: 599–607, Bibcode:1962AJ.....67..599W, doi:10.1086/108791  The data is from Orbit #3; the solution used by the 6th Washington Double Star catalogue for WDS 14514+1906.
  4. ^ a b c d e f Fernandes, J. et al. (1998), "Fundamental stellar parameters for nearby visual binary stars: eta Cas, XI Boo, 70 OPH and 85 Peg", Astronomy and Astrophysics 338: 455–464, Bibcode:1998A&A...338..455F 
  5. ^ a b c d Wood, Brian E.; Linsky, Jeffrey L. (July 2010), "Resolving the ξ Boo Binary with Chandra, and Revealing the Spectral Type Dependence of the Coronal "FIP Effect"", The Astrophysical Journal 717 (2): 1279–1290, arXiv:1005.3281, Bibcode:2010ApJ...717.1279W, doi:10.1088/0004-637X/717/2/1279 
  6. ^ a b Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008), "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics", The Astrophysical Journal 687 (2): 1264–1293, arXiv:0807.1686, Bibcode:2008ApJ...687.1264M, doi:10.1086/591785 
  7. ^ Hinshaw, Gary (February 3, 1997), Science Requirements Document (PDF), NASA JPL, archived from the original on 2006-05-29, retrieved 2006-08-10 
  8. ^ Holmes, E. K. et al. (2003), "A Survey of Nearby Main-Sequence Stars for Submillimeter Emission", The Astronomical Journal 125 (6): 3334–3343, Bibcode:2003AJ....125.3334H, doi:10.1086/375202 

External links[edit]