Epsilon Columbae

ε Columbae
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Columba
Right ascension 05h 31m 12.74899s[1]
Declination −35° 28′ 13.8605″[1]
Apparent magnitude (V) 3.87[2]
Characteristics
Spectral type K1 II/III[3] or K1 IIIa[4]
U−B color index +1.08[2]
B−V color index +1.14[2]
Astrometry
Radial velocity (Rv)−4.9[5] km/s
Proper motion (μ) RA: +26.421[1] mas/yr
Dec.: −30.085[1] mas/yr
Parallax (π)12.4610 ± 0.2423 mas[1]
Distance262 ± 5 ly
(80 ± 2 pc)
Absolute magnitude (MV)−0.67[6]
Details
Mass2.47[7] M☉
Radius25.2+3.1
−2.0[1] R☉
Luminosity251.2±5.6[1] L☉
Surface gravity (log g)2.05[4] cgs
Temperature4,575+195
−260[1] K
Metallicity [Fe/H]−0.03[4] dex
Age1.53[7] Gyr
Other designations
ε Col, CD−35° 2348, FK5 2413, HD 36597, HIP 25859, HR 1862, SAO 195924[8]
Database references
SIMBADdata

Epsilon Columbae, Latinized from ε Columbae, is a star in the southern constellation of Columba. It is visible to the naked eye, having an apparent visual magnitude of 3.87.[2] Based upon an annual parallax shift of 12.46 mas,[1] it is located approximately 262 light years distant from the Sun. The star is drifting closer with a radial velocity of −5 km/s.[5]

This is an orange-hued[9] K-type giant star with a stellar classification of K1 II/III.[3] At the age of 1.5[7] billion years old, it has exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. Epsilon Columbae has 2.5[7] times the mass and 25[1] times the radius of the Sun. The star radiates 251 times the solar luminosity from its enlarged photosphere at an effective temperature of 4,575 K.[1] It has a peculiar velocity of 30.0±3.9 km/s, making it a candidate runaway star system.[10] Based upon changes in the star's movement, it has an orbiting stellar companion of unknown type.[11]

  1. ^ a b c d e f g h i j k Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Johnson1966 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1982 was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference luck2015 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 Cite error: The named reference Luck2015 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Kambic2009 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).