Tau3 Eridani, Latinized from τ3 Eridani, is a star in the constellation Eridanus. It is visible to the naked eye with an apparent visual magnitude of 4.10.[2] Using the parallax method,[1] the distance to this star can be estimated as 88.6 light years. In 2001 it was reported as a candidate Vega-like star, meaning it appears to radiate an infrared excess from an orbiting circumstellar disk.[11] However, this has not been confirmed.[12]

τ3 Eridani
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Eridanus
Right ascension 03h 02m 23.49939s[1]
Declination −23° 37′ 28.0936″[1]
Apparent magnitude (V) 4.10[2]
Characteristics
Spectral type A3 IV-V[3]
U−B color index +0.08[2]
B−V color index +0.16[2]
Astrometry
Radial velocity (Rv)−9.8[4] km/s
Proper motion (μ) RA: −147.25[1] mas/yr
Dec.: −55.28[1] mas/yr
Parallax (π)36.80 ± 0.18 mas[1]
Distance88.6 ± 0.4 ly
(27.2 ± 0.1 pc)
Absolute magnitude (MV)+1.91[5]
Details
Mass1.78[6] M
Radius1.9[7] R
Luminosity13.7[8] L
Surface gravity (log g)4.17[6] cgs
Temperature8,251±281[6] K
Metallicity [Fe/H]−0.21[3] dex
Rotational velocity (v sin i)133[9] km/s
Age476[6] Myr
Other designations
τ3 Eridani, τ3 Eri, 11 Eridani, CD-24° 1387, HD 18978, HIP 14146, HR 919, SAO 168249.[10]
Database references
SIMBADdata

This is an A-type star with a stellar classification of A3 IV-V.[3] The luminosity class of IV-V indicates the spectrum displays traits intermediate between a main sequence and subgiant star. It is around 476[6] million years old and is spinning rapidly with a projected rotational velocity of 133 km/s.[9] This is creating an equatorial bulge that might be 7% wider than the polar radius.[13] Tau3 Eridani has 178%[6] of the Sun's mass and nearly double the radius of the Sun.[7] The star shines with 13.7 times the solar luminosity from an outer atmosphere at an effective temperature of 8,251 K.[6]

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, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
  2. ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
  3. ^ a b c Gray, R. O.; et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
  4. ^ Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institute of Washington, D.C., Bibcode:1953GCRV..C......0W.
  5. ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  6. ^ a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (May 2015), "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 38, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607, 146.
  7. ^ a b 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.
  8. ^ 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.
  9. ^ a b Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298.
  10. ^ "tau03 Eri". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-10-13.{{cite web}}: CS1 maint: postscript (link)
  11. ^ Song, Inseok; et al. (January 2001), "Ages of A-Type Vega-like Stars from uvbyβ Photometry", The Astrophysical Journal, 546 (1): 352–357, arXiv:astro-ph/0010102, Bibcode:2001ApJ...546..352S, doi:10.1086/318269, S2CID 18154947.
  12. ^ Gáspár, András; et al. (May 2013), "The Collisional Evolution of Debris Disks", The Astrophysical Journal, 768 (1): 29, arXiv:1211.1415, Bibcode:2013ApJ...768...25G, doi:10.1088/0004-637X/768/1/25, S2CID 119295265, 25.
  13. ^ Van Belle, Gerard T. (2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review, 20 (1): 51, arXiv:1204.2572, Bibcode:2012A&ARv..20...51V, doi:10.1007/s00159-012-0051-2, S2CID 119273474.