Tau1 Aquarii

For other star systems with this Bayer designation, see Tau Aquarii.
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
SIMBADdata

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]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference mnrassa27_11 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference aass34_1 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference wilson1953 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b c d e f g h Cite error: The named reference Zorec_Royer_2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference aaa367_521 was invoked but never defined (see the help page).
  9. ^ a b c Cite error: The named reference apjl730_2_L29 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton_Tokovinin_2008 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Curtis_et_al_2019 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Wraight_et_al_2012 was invoked but never defined (see the help page).