Tau1 Aquarii

For other star systems with this Bayer designation, see Tau Aquarii.
Tau1 Aquarii
Diagram showing star positions and boundaries of the Aquarius constellation and its surroundings


Location of τ1 Aquarii (circled)

Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 22h 47m 42.76932s[1]
Declination –14° 03′ 23.1409″[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: +30.61[1] mas/yr
Dec.: –9.23[1] mas/yr
Parallax (π)10.27 ± 0.46[1] mas
Distance320 ± 10 ly
(97 ± 4 pc)
Details
Radius2.0[6] R☉
Age100[7] Myr
Other designations
69 Aquarii, ADS 16268, BD–14 6346, HD 215766, HIP 112542, HR 8673, SAO 165298.[8]
Data sources:
Hipparcos Catalogue,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.)

Tau1 Aquarii (τ1 Aqr, τ1 Aquarii) is the Bayer designation for a 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 320 light-years (98 parsecs) from Earth.[1]

τ1 Aquarii has a stellar classification of B9 V;[3] right along the borderline between a B- and A-type main sequence star. It is around 100[7] million years old and has twice the Sun's radius.[6] When examined in the infrared band, it displays an excess emission that is a characteristic of stars with an orbiting debris disk. Indeed, the model that best fits the data suggests there are two concentric circumstellar disks.[7]

References

  1. 1 2 3 4 5 6 van Leeuwen, F. (November 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.
  2. 1 2 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. 1 2 Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
  4. 1 2 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. ↑ Wilson, Ralph Elmer (1953), General catalogue of stellar radial velocities, Carnegie Institution of Washington, Bibcode:1953QB901.W495......
  6. 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: 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451.
  7. 1 2 3 Morales, Farisa Y.; et al. (April 2011), "Common Warm Dust Temperatures Around Main-sequence Stars", The Astrophysical Journal Letters 730 (2): L29, Bibcode:2011ApJ...730L..29M, doi:10.1088/2041-8205/730/2/L29.
  8. ↑ "69 Aqr -- Star in double system", SIMBAD Astronomical Object Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-07-03.

External links

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