Lambda Columbae

λ Columbae

File:LambdaColLightCurve.png A light curve for Lambda Columbae, plotted from TESS data. The 0.64 day period is marked in red.
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Columba
Right ascension	Template:RA
Declination	Template:DEC
Apparent magnitude (V)	4.86
Characteristics
Spectral type	B5 V
U−B Template:Engvar	−0.57
B−V Template:Engvar	−0.15
Variable type	Suspected rotating ellipsoidal
Astrometry
Radial velocity (Rv)	+30.0 km/s
Proper motion (μ)	RA: −4.72 mas/yr Dec.: +31.32 mas/yr
Parallax (π)	9.75±0.21 mas
Distance	Template:Rnd ± Template:Rnd ly (Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)	−0.17
Details
Mass	Template:Solar mass
Radius	3.4 Template:Solar radius
Luminosity	213 Template:Solar luminosity
Surface gravity (log g)	4.22 cgs
Temperature	13,524 K
Metallicity [Fe/H]	−0.06 dex
Rotational velocity (v sin i)	88 km/s
Age	Myr
Metallicity [Fe/H]	{{{metal_fe2}}} dex
Other designations
λ Col, CD−33°2599, HD 39764, HIP 27810, HR 2056, SAO 196276.
Database references
SIMBAD	data

Lambda Columbae, Latinized from λ Columbae, is a probable binary star in the southern constellation of Columba. With an apparent visual magnitude of 4.86, it is faintly visible to the naked eye. The measured annual parallax shift of 9.75 mas yields an estimated distance of roughly 335 light years.

Lambda Columbae has a stellar classification of B5 V, indicating that it is a B-type main sequence star. It is a suspected rotating ellipsoidal variable with a period of 0.64 days and an amplitude of 0.07 magnitude. Confirmation would indicate that this is a close binary system. It has an estimated age of around 57 million years.

In Chinese, (), meaning Son, refers to an asterism consisting of λ Columbae and β Columbae. Consequently, λ Columbae itself is known as (, Template:Langx.). From this Chinese name, the name Tsze is derived.