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Tau Sculptoris
Observation data
Epoch J2000.0       Equinox J2000.0 ( ICRS)
Constellation Sculptor
Right ascension 01h 36m 08.50799s [1]
Declination −29° 54′ 26.3540″ [1]
Apparent magnitude (V) +5.69 [2] (6.06 + 7.35) [3]
Characteristics
Spectral type F2 V [4]
B−V color index +0.33 [2]
Astrometry
Radial velocity (Rv)+3.00±4.50 [5] km/s
Proper motion (μ) RA: +117.37 [1]  mas/ yr
Dec.: +46.72 [1]  mas/ yr
Parallax (π)14.42 ± 0.81  mas [1]
Distance230 ± 10  ly
(69 ± 4  pc)
Absolute magnitude (MV)2.04 + 3.02 [6]
Orbit [6]
Period (P)1503.58 ± 35.32 yr
Semi-major axis (a)3.155±0.132
Eccentricity (e)0.604±0.019
Inclination (i)55.6±0.8°
Longitude of the node (Ω)69.6±0.8°
Periastron epoch (T)2039.79 ± 33.80
Argument of periastron (ω)
(secondary)
140.2±2.8°
Details
τ Her A
Mass1.56 [7]  M
Surface gravity (log g)3.96±0.14 [7]  cgs
Temperature7,155±243 [7]  K
Metallicity [Fe/H]−0.12 [8]  dex
Rotational velocity (v sin i)73.8±7.8 [9] km/s
Age1.284 [7]  Gyr
τ Her B
Mass1.37 [6]  M
Other designations
τ Scl, CD−30° 540, HD 9906, HIP 7463, HR 462, SAO 193201, WDS J01361-2954 [10]
Database references
SIMBAD data

Tau Sculptoris (τ Scl, τ Sculptoris) is a binary star [6] system in the southern constellation of Sculptor, about 8° to the east-southeast of Alpha Sculptoris. [11] It is faintly visible to the naked eye with a combined apparent visual magnitude of +5.69. [2] Based upon an annual parallax shift of 14.42  mas as seen from Earth, [1] it is located around 230  light years from the Sun.

The binary nature of this system was discovered by English astronomer John Herschel in 1835. The current orbital elements are based upon a fraction of a single orbit, as the estimated orbital period is around 1,503 years. The system has a semimajor axis of 3.2  arc seconds and an eccentricity of 0.6. [6] The primary member, component A, is a yellow-white hued F-type main sequence star with an apparent magnitude of +6.06 [3] and a stellar classification of F2 V. [4] The companion, component B, is a magnitude 7.35 star. [3]

References

  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 Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode: 1966CoLPL...4...99J.
  3. ^ a b c 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.
  4. ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode: 1982mcts.book.....H.
  5. ^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv: 1208.3048, Bibcode: 2012A&A...546A..61D, doi: 10.1051/0004-6361/201219219, S2CID  59451347, A61.
  6. ^ a b c d e Cvetkovic, Z.; Novakovic, B. (December 2006), "Orbits For Sixteen Binaries", Serbian Astronomical Journal, 173 (173): 73–82, Bibcode: 2006SerAJ.173...73C, doi: 10.2298/SAJ0673073C.
  7. ^ a b c d David, Trevor J.; Hillenbrand, Lynne A. (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): 146, arXiv: 1501.03154, Bibcode: 2015ApJ...804..146D, doi: 10.1088/0004-637X/804/2/146, S2CID  33401607.
  8. ^ Casagrande, L.; et al. (2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy & Astrophysics, 530 (A138): 21, arXiv: 1103.4651, Bibcode: 2011A&A...530A.138C, doi: 10.1051/0004-6361/201016276, S2CID  56118016.
  9. ^ Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics, 542: A116, arXiv: 1204.2459, Bibcode: 2012A&A...542A.116A, doi: 10.1051/0004-6361/201118724, S2CID  53666672.
  10. ^ "tau Scl". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-04-11.{{ cite web}}: CS1 maint: postscript ( link)
  11. ^ O'Meara, Steve (2007), Herschel 400 Observing Guide, Cambridge University Press, p. 302, ISBN  978-0521858939.