Tau Cassiopeiae

Tau Cassiopeiae

Map of the Bayer-designated stars in Cassiopeia. Tau Cassiopeiae is circled.
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cassiopeia
Right ascension 00h 55m 00.15523s[1]
Declination +58° 58′ 21.7108″[1]
Apparent magnitude (V) +4.86[2]
Characteristics
Spectral type K1 IIIa[3]
U−B color index +1.05[2]
B−V color index +1.11[2]
Variable type Suspected[4]
Astrometry
Radial velocity (Rv)−20.48±0.31[5] km/s
Proper motion (μ) RA: +60.81±0.19[1] mas/yr
Dec.: +56.47±0.17[1] mas/yr
Parallax (π)18.75 ± 0.20 mas[1]
Distance174 ± 2 ly
(53.3 ± 0.6 pc)
Absolute magnitude (MV)1.269[6]
Details
Mass1.44[7] M☉
Radius10[5] R☉
Luminosity40[7] L☉
Surface gravity (log g)2.50±0.09[8] cgs
Temperature4,617±77[7] K
Metallicity [Fe/H]+0.06±0.06[8] dex
Rotational velocity (v sin i)5.9[5] km/s
Age3.90[7] Gyr
Other designations
τ Cas, 5 Cas, BD+57° 2804, FK5 3909, HD 223165, HIP 117301, HR 9008, SAO 35763[9]
Database references
SIMBADdata

Tau Cassiopeiae (τ Cassiopeiae) is a solitary,[10] orange hued star in the northern constellation of Cassiopeia. It is bright enough to be seen with the naked eye, having an apparent visual magnitude of +4.86.[2] Based upon an annual parallax shift of 18.75 mas as seen from Earth,[1] this system is located about 174 light years from the Sun.

The spectrum of this star indicates it is an evolved, K-type giant star with a stellar classification of K1 IIIa.[3] It is a suspected variable star of unknown type.[4][11] Tau Cassiopeiae is 3.9[7] billion years old with about 1.44[7] times the mass of the Sun and 10[5] times the Sun's radius. It is radiating 40[7] times the Sun's luminosity from its expanded photosphere at an effective temperature of around 4,617 K.[7]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Argue1966 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference perkins1989 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Halbedel1993 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference Massarotti2008 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Soubiran2008 was invoked but never defined (see the help page).
  7. ^ a b c d e f g h Cite error: The named reference luck2015 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Wu2010 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Halbedel1989 was invoked but never defined (see the help page).