Tau Cancri

Tau Cancri
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cancer
Right ascension 09h 08m 00.04963s[1]
Declination +29° 39′ 15.2428″[1]
Apparent magnitude (V) +5.42[2]
Characteristics
Spectral type G8 III[3]
U−B color index +0.57[2]
B−V color index +0.89[2]
Astrometry
Radial velocity (Rv)−13.90±0.14[4] km/s
Proper motion (μ) RA: −32.51[1] mas/yr
Dec.: +2.79[1] mas/yr
Parallax (π)11.92 ± 0.39 mas[1]
Distance274 ± 9 ly
(84 ± 3 pc)
Absolute magnitude (MV)+0.81[5]
Details[4]
Mass2.42±0.09 M☉
Radius7.76±0.51 R☉
Luminosity40 L☉
Surface gravity (log g)3.21 cgs
Temperature5,153 K
Metallicity [Fe/H]−0.06 dex
Rotational velocity (v sin i)1.95±0.45 km/s
Age620±60 Myr
Other designations
τ Cnc, 72 Cancri, BD+30° 1817, FK5 2719, HD 78235, HIP 44818, HR 3621, SAO 80650[6]
Database references
SIMBADdata

Tau Cancri (τ Cancri) is a solitary,[3] yellow-hued star in the zodiac constellation of Cancer. With an apparent visual magnitude of +5.42,[2] it is faintly visible to the naked eye. Based upon an annual parallax shift of 11.92 mas as seen from Earth,[1] it is located around 274 light-years from the Sun.

With an age of about 620[4] million years and a stellar classification of G8 III,[3] this is a red-clump giant star,[7] which indicates that it has evolved onto the horizontal branch and is generating energy through helium fusion at its core. It is a microvariable, showing a luminosity variation of 0.04 in magnitude.[8] Tau Cancri has an estimated 2.4 times the mass of the Sun and 7.8 times the Sun's radius. The star radiates 40 times the solar luminosity from its photosphere at an effective temperature of 5,153 K.[4]

  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 Argue1963 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference Jofre2015 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference DaSilva2015 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Adelman2001 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Adelman2000 was invoked but never defined (see the help page).