Epsilon Columbae

ε Columbae
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Columba
Right ascension 05h 31m 12.74899s
Declination −35° 28 13.8605
Apparent magnitude (V) 3.87
Characteristics
Spectral type K1 II/III or K1 IIIa
U−B color index +1.08
B−V color index +1.14
Astrometry
Radial velocity (Rv)−4.9 km/s
Proper motion (μ) RA: +26.421 mas/yr
Dec.: −30.085 mas/yr
Parallax (π)12.4610±0.2423 mas
Distance262 ± 5 ly
(80 ± 2 pc)
Absolute magnitude (MV)−0.67
Details
Mass2.47 M
Radius25.2+3.1
−2.0
 R
Luminosity251.2±5.6 L
Surface gravity (log g)2.05 cgs
Temperature4,575+195
−260
 K
Metallicity [Fe/H]−0.03 dex
Age1.53 Gyr
Other designations
ε Col, CD−35°2348, FK5 2413, HD 36597, HIP 25859, HR 1862, SAO 195924
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. Based upon an annual parallax shift of 12.46 mas, it is located approximately 262 light years distant from the Sun. The star is drifting closer with a radial velocity of −5 km/s.

This is an orange-hued K-type giant star with a stellar classification of K1 II/III. At the age of 1.5 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 times the mass and 25 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. It has a peculiar velocity of 30.0±3.9 km/s, making it a candidate runaway star system. Based upon changes in the star's movement, it has an orbiting stellar companion of unknown type.