Xi Columbae

Xi Columbae is a binary star^[5] system in the southern constellation of Columba. With an apparent visual magnitude of 4.97,^[2] it is faintly visible to the naked eye. Based upon an annual parallax shift of 10.1 mas,^[1] it is located around 323 light years from the Sun. The system is a member of the HR 1614 supergroup,^[7] and is drifting further away with a radial velocity of +59.5 km/s,^[4]

Xi Columbae

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Columba
Right ascension	05h 55m 29.91038s[1]
Declination	−37° 07′ 14.3232″[1]
Apparent magnitude (V)	4.97[2]
Characteristics
Spectral type	K1 III CNII[3]
B−V color index	+1.096[2]
Astrometry
Radial velocity (Rv)	+59.5[4] km/s
Proper motion (μ)	RA: +38.020[1] mas/yr Dec.: −23.491[1] mas/yr
Parallax (π)	10.0920±0.1408 mas[1]
Distance	323 ± 5 ly (99 ± 1 pc)
Absolute magnitude (MV)	−0.05[5]
Orbit[5]
Period (P)	1420.6 d
Semi-major axis (a)	3.60 AU
Eccentricity (e)	0.39
Semi-amplitude (K1) (primary)	5.68 km/s
Details
Radius	16.23+0.14 −2.27[1] R☉
Luminosity	120±2[1] L☉
Surface gravity (log g)	2.26[2] cgs
Temperature	4,743+372 −20[1] K
Metallicity [Fe/H]	+0.29[2] dex
Rotational velocity (v sin i)	2.6[5] km/s
Other designations
ξ Col, CD−37°2487, HD 40176, HIP 28010, HR 2087, SAO 196316[6]
Database references
SIMBAD	data

This is an astrometric binary^[8] with an orbital period of 1,420.6 days and an eccentricity of 0.39.^[5] The primary is an evolved K-type giant star with a stellar classification of K1 III CNII,^[3] showing an overabundance of CN in its spectrum. The star has expanded to 16 times the radius of the Sun and is radiating 120 times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,743 K.^[1] The companion has a mass of at least 59% that of the Sun.^[5]