Alpha Lupi

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Alpha Lupi
Observation data
Epoch J2000
Constellation
(pronunciation)
Lupus
Right ascension 14h 41m 55.8s
Declination -47° 23′ 18″
Apparent magnitude (V) 2.30
Characteristics
Spectral type B1.5 III
U-B color index -0.89
B-V color index -0.20
Variable type Beta Cephei
Astrometry
Radial velocity (Rv) 5 km/s
Proper motion (μ) RA: -21.15 mas/yr
Dec.: -24.22 mas/yr
Parallax (π) 5.95 ± 0.76 mas
Distance approx. 550 ly
(approx. 170 pc)
Absolute magnitude (MV) -3.83
Details
Mass 10–11 M
Radius 10 R
Luminosity 18,000 L
Temperature 21,600 K
Metallicity ?
Rotation 24 km/s.
Age 2 × 107 years
Other designations
Kakkab, HR 5469, CD -46°9501, HD 129056, SAO 225128, FK5 541, CPD P-46 6927, HIP 71860.

Alpha Lupi (α Lup / α Lupi) is a star in the constellation Lupus. It is called the traditional Chinese name Men, and sometimes by the Arabic name Kakkab, which means "Guide Star" or "Star of Fortune".


It is a Beta Cephei variable with a period of just over 6 hours, 14 minutes, and the magnitude varies by about 0.03, or about 3% of the total luminosity. A small star situated near Alpha Lupi may just be an optical companion.