Sigma Columbae

Sigma Columbae, Latinized from σ Columbae, is a solitary,^[10] yellow-white hued star in the southern constellation of Columba. It is faintly visible to the naked eye with an apparent visual magnitude of 5.51.^[2] Based upon an annual parallax shift of 1.96 mas as seen from Earth,^[1] this star is located roughly 1,700 light years from the Sun.

Sigma Columbae

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Columba
Right ascension	05h 56m 20.94287s[1]
Declination	−31° 22′ 56.7846″[1]
Apparent magnitude (V)	5.51[2]
Characteristics
Spectral type	F2 III[3]
B−V color index	+0.39[2]
Astrometry
Radial velocity (Rv)	+19.4±2.9[4] km/s
Proper motion (μ)	RA: +0.08[1] mas/yr Dec.: +6.04[1] mas/yr
Parallax (π)	1.96±0.24 mas[1]
Distance	approx. 1,700 ly (approx. 510 pc)
Absolute magnitude (MV)	−2.98[5]
Details
Mass	3.79[6] M☉
Luminosity	1,312[7] L☉
Surface gravity (log g)	2.02[6] cgs
Temperature	6,820[8] K
Metallicity [Fe/H]	−0.91[6] dex
Rotational velocity (v sin i)	73.4±3.7[8] km/s
Age	400[6] Myr
Other designations
σ Col, CD−31°2848, HD 40248, HIP 28098, HR 2092, SAO 196330[9]
Database references
SIMBAD	data

At an age of about 400 million years,^[6] the spectrum of this star suggests this is an evolved F-type giant with a stellar classification of F2 III.^[3] It is spinning with a projected rotational velocity of about 74 km/s,^[8] which is giving the star an oblate shape with an equatorial bulge that is 10% larger than the polar radius.^[11] It has 3.79^[6] times the mass of the Sun and is radiating 1,312^[7] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 6,820 K.^[8]