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Xi Eridani

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ξ Eridani
Location of ξ Eridani (circled in red)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Eridanus
Right ascension 04h 23m 40.85270s[1]
Declination −03° 44 43.6771[1]
Apparent magnitude (V) 5.17[2]
Characteristics
Evolutionary stage main sequence[3]
Spectral type A2 V[4]
U−B color index +0.08[2]
B−V color index +0.08[2]
Astrometry
Radial velocity (Rv)−11.0[5] km/s
Proper motion (μ) RA: −47.36[1] mas/yr
Dec.: −54.91[1] mas/yr
Parallax (π)15.60±0.25 mas[1]
Distance209 ± 3 ly
(64 ± 1 pc)
Absolute magnitude (MV)+1.59[6]
Details
Mass2.29[7] M
Radius2.2[8] R
Luminosity27.6[9] L
Surface gravity (log g)3.73[10] cgs
Temperature8,400[9] K
Rotational velocity (v sin i)194.3±2.3[4] km/s
Age450[7] Myr
Other designations
ξ Eri, BD−04°818, 42 Eridani, FK5 1120, HD 27861, HIP 20507, HR 1383, SAO 131176[11]
Database references
SIMBADdata

ξ Eridani (Latinised as Xi Eridani) is a solitary[7] star in the constellation Eridanus. With an apparent visual magnitude of 5.17,[2] it is faintly visible to the naked eye on a clear, dark night. Based upon an annual parallax shift of 0.00156 arcseconds,[1] it is located around 209 light years from the Sun. The star is considered a member of the Sirius supercluster.[6]

This is an ordinary A-type main sequence star with a stellar classification of A2 V,[4] indicating that it is generating energy through the thermonuclear fusion of hydrogen into helium in its core region. It is around 450[7] million years old and has a relatively high rate of rotation with a projected rotational velocity of 194 km/s.[4] The star has about 2.3 times the mass of the Sun,[7] 2.2 times the Sun's radius,[8] and radiates 27.6[9] times the solar luminosity from its outer atmosphere at an effective temperature of 8,400 K.[9]

References

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  1. 1 2 3 4 5 6 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, S2CID 18759600.
  2. 1 2 3 4 Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", SIMBAD, Bibcode:1986EgUBV........0M.
  3. Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy and Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691.
  4. 1 2 3 4 Díaz, C. G.; et al. (July 2011), "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum", Astronomy & Astrophysics, 531: A143, arXiv:1012.4858, Bibcode:2011A&A...531A.143D, doi:10.1051/0004-6361/201016386, S2CID 119286673.
  5. Wielen, R.; et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions", Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg, 35, Veröffentlichungen des Astronomisches Rechen-Institut Heidelberg: 1, Bibcode:1999VeARI..35....1W.
  6. 1 2 Eggen, Olin J. (August 1998), "The Sirius Supercluster and Missing Mass near the Sun", The Astronomical Journal, 116 (2): 782–788, Bibcode:1998AJ....116..782E, doi:10.1086/300465.
  7. 1 2 3 4 5 De Rosa, R. J.; et al. (January 2014), "The VAST Survey – III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216–1240, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932.
  8. 1 2 Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) – Third edition – Comments and statistics", Astronomy and Astrophysics, 367 (2): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
  9. 1 2 3 4 McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
  10. King, Jeremy R.; et al. (April 2003), "Stellar Kinematic Groups. II. A Reexamination of the Membership, Activity, and Age of the Ursa Major Group", The Astronomical Journal, 125 (4): 1980–2017, Bibcode:2003AJ....125.1980K, doi:10.1086/368241.
  11. "* ksi Eri". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-11-03.