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τ1 Aquarii
Location of τ1 Aquarii (circled)
Observation data
Epoch J2000       Equinox J2000
Constellation Aquarius
Right ascension 22h 47m 42.76996s [1]
Declination –14° 03′ 23.1419″ [1]
Apparent magnitude (V) +5.66 [2]
Characteristics
Spectral type B9 V [3]
U−B color index –0.25 [4]
B−V color index –0.05 [4]
Astrometry
Radial velocity (Rv)+15 [5] km/s
Proper motion (μ) RA: +29.960 [1]  mas/ yr
Dec.: –9.009 [1]  mas/ yr
Parallax (π)9.1849 ± 0.1301  mas [1]
Distance355 ± 5  ly
(109 ± 2  pc)
Absolute magnitude (MV)+0.74 [6]
Details
Mass2.68±0.05 [7]  M
Radius2.0 [8]  R
Luminosity63.5 [7]  L
Temperature10,617 [7]  K
Rotational velocity (v sin i)185 [7] km/s
Age100 [9]  Myr
Other designations
τ1 Aqr, 69 Aquarii, BD–14 6346, GC 31802, HD 215766, HIP 112542, HR 8673, SAO 165298, ADS 16268, WDS J22477-1403A [10]
Database references
SIMBAD data

Tau1 Aquarii, Latinized from τ1 Aquarii, is the Bayer designation for a single [11] star in the equatorial constellation of Aquarius. With an apparent visual magnitude of 5.66, [2] it is a faint naked eye that requires dark suburban skies for viewing. Parallax measurements made during the Hipparcos mission yield a distance estimate of roughly 355 light-years (109 parsecs) from Earth. [1] The star is drifting further away with a radial velocity of +15 km/s. [5] It is a candidate member of the Pisces-Eridanus stellar stream. [12]

The stellar classification of τ1 Aquarii is B9 V; [3] right along the borderline between a B- and A-type main sequence star. This is a candidate silicon star; a type of Ap star of class CP2 that shows a magnetic field. [13] It is around 100 [9] million years old and is spinning rapidly with a projected rotational velocity of 185 km/s. [7] The star has 2.7 [7] times the mass of the Sun and double the Sun's radius. [8] It is radiating 63.5 [7] times the luminosity of the Sun from its photosphere at an effective temperature of 10,617 K. [7] When examined in the infrared band, it displays an excess emission that is a characteristic of stars with an orbiting debris disk. The model that best fits the data suggests there are two concentric circumstellar disks. [9]

References

  1. ^ a b c d e f 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 Corben, P. M.; Stoy, R. H. (1968), "Photoelectric Magnitudes and Colours for Bright Southern Stars", Monthly Notes of the Astronomical Society of Southern Africa, 27: 11, Bibcode: 1968MNSSA..27...11C.
  3. ^ a b Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode: 1988mcts.book.....H.
  4. ^ a b Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series, 34: 1–49, Bibcode: 1978A&AS...34....1N.
  5. ^ a b Wilson, Ralph Elmer (1953), "General catalogue of stellar radial velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institution of Washington, Bibcode: 1953GCRV..C......0W.
  6. ^ 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.
  7. ^ a b c d e f g h Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv: 1201.2052, Bibcode: 2012A&A...537A.120Z, doi: 10.1051/0004-6361/201117691, S2CID  55586789.
  8. ^ 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.
  9. ^ a b c Morales, Farisa Y.; et al. (April 2011), "Common Warm Dust Temperatures Around Main-sequence Stars" (PDF), The Astrophysical Journal Letters, 730 (2): L29, Bibcode: 2011ApJ...730L..29M, doi: 10.1088/2041-8205/730/2/L29, S2CID  2360696.
  10. ^ "* tau01 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-03.
  11. ^ 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.
  12. ^ Curtis, Jason L.; et al. (August 2019), "TESS Reveals that the Nearby Pisces-Eridanus Stellar Stream is only 120 Myr Old", The Astronomical Journal, 158 (2): 11, arXiv: 1905.10588, Bibcode: 2019AJ....158...77C, doi: 10.3847/1538-3881/ab2899, S2CID  166228270, 77.
  13. ^ Wraight, K. T.; et al. (2012), "A photometric study of chemically peculiar stars with the STEREO satellites - I. Magnetic chemically peculiar stars★", Monthly Notices of the Royal Astronomical Society, 420 (1): 757–772, arXiv: 1110.6283, Bibcode: 2012MNRAS.420..757W, doi: 10.1111/j.1365-2966.2011.20090.x, S2CID  14811051.

External links