Tau3 Gruis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Grus
Right ascension 22h 56m 47.80007s[1]
Declination −47° 58′ 09.1992″[1]
Apparent magnitude (V) 5.71[2]
Characteristics
Spectral type kA5hA7mF2[3]
U−B color index +0.17[2]
B−V color index +0.22[2]
Astrometry
Radial velocity (Rv)6.3±0.6[4] km/s
Proper motion (μ) RA: −24.942[1] mas/yr
Dec.: +2.848[1] mas/yr
Parallax (π)12.3180 ± 0.1170 mas[1]
Distance265 ± 3 ly
(81.2 ± 0.8 pc)
Absolute magnitude (MV)+1.36[5]
Details
Radius2.88+0.13
−0.18[1] R☉
Luminosity26.8+0.3
−0.3[1] L☉
Temperature7,735+406
−158[1] K
Other designations
τ Gru, CD−48°14364, FK5 3832, HD 216823, HIP 113307, HR 8722, SAO 231364[6]
Database references
SIMBADdata

Tau3 Gruis is a solitary[7] star in the southern constellation of Grus. Its apparent magnitude is 5.71,[2] which is bright enough to be visible to the naked eye as a dim, white-hued star. The star is located around 265 light-years (81 pc) distant from the Sun based on parallax, and it is drifting further away with a radial velocity of 6 km/s.[4]

This is an Am star[8] with a stellar classification of kA5hA7mF2.[3] This notation indicates the spectrum displays the calcium K-line of an A5 star, the hydrogen lines of an A7 star, and the metal lines of an F2 star.[9] It has 2.9[1] times the Sun's radius and is radiating 27[1] times the luminosity of the Sun from its photosphere at an effective temperature of around 7,735 K.[1]

References

  1. ^ a b c d e f g h i j k Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d Feinstein, A. (1974), "Photoelectric UBVRI observations of Am stars", Astronomical Journal, 79: 1290, Bibcode:1974AJ.....79.1290F, doi:10.1086/111675.
  3. ^ a b Abt, Helmut A.; Morrell, Nidia I. (1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement, 99: 135, Bibcode:1995ApJS...99..135A, doi:10.1086/192182
  4. ^ a b Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
  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. ^ "tau03 Gru". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-24.((cite web)): CS1 maint: postscript (link)
  7. ^ 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, S2CID 14878976.
  8. ^ Renson, P.; Manfroid, J. (2009), "Catalogue of Ap, HgMn and Am stars", Astronomy and Astrophysics, 498 (3): 961–966, Bibcode:2009A&A...498..961R, doi:10.1051/0004-6361/200810788.
  9. ^ Gray, Richard O.; Corbally, J. (2009), Stellar Spectral Classification, Princeton University Press, p. 178, ISBN 978-0691125114.
Categories