T Ceti

Not to be confused with τ (tau) Ceti.
T Ceti

A light curve for T Ceti, ploted from ASAS data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Cetus
Right ascension 00h 21m 46.27529s[2]
Declination −20° 03′ 28.9098″[2]
Apparent magnitude (V) 5.61[3] (5.0 - 6.9)[4]
Characteristics
Spectral type M5-6Se[5]
B−V color index 1.58±0.03[3]
Variable type SRc[6]
Astrometry
Radial velocity (Rv)+28.9±0.9[7] km/s
Proper motion (μ) RA: +59.665[2] mas/yr
Dec.: −10.229[2] mas/yr
Parallax (π)3.70 ± 0.47 mas[8]
Distanceapprox. 900 ly
(approx. 270 pc)
Absolute magnitude (MV)−1.51[3]
Details[6]
Mass3.0±0.3 M☉
Radius275±34 R☉
Luminosity8,128+2,587
−1,962 L☉
Surface gravity (log g)0.01±0.11 cgs
Temperature3,396+103
−100 K
Metallicity [Fe/H]0.0 dex
Other designations
T Cet, BD−20°50, HD 1760, HIP 1728, HR 85, SAO 166210[9]
Database references
SIMBADdata

T Ceti is a semiregular variable star located in the equatorial constellation of Cetus. It varies between magnitudes 5.0 and 6.9 over 159.3 days.[4] The stellar parallax shift measured by Hipparcos is 3.7 mas,[8] which yields a distance estimate of roughly 900 light years. It is moving further from the Earth with a heliocentric radial velocity of +29 km/s.[7]

This is an MS-type star on the asymptotic giant branch with a spectral type of M5-6Se.[5] (The 'e' notation indicates the presence of emission lines in the spectrum). The star is losing mass at the rate of 8.2×10−8 M☉ y−1,[10] and it is surrounded by a circumstellar dust shell consisting of crystallized, mostly iron-rich silicates.[11]

T Ceti has an estimated three times the mass of the Sun and has expanded to 275 times the Sun's radius. It is radiating 8,128 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,396 K.[6]

  1. ^ Cite error: The named reference ASASServer was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference gcvs was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference keenan1954 was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference Cruzalebes2013 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference vanLeeuwen2007 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 Wallerstein2011 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Niyogi2011 was invoked but never defined (see the help page).