Epoch J2000 Equinox J2000
|Right ascension||12h 29m 51.85517s|
|Declination||−16° 30′ 55.5525″|
|Apparent magnitude (V)||+2.962|
|Spectral type||A0 IV(n) kB9|
|U−B color index||−0.050|
|B−V color index||−0.045|
|Radial velocity (Rv)||+9 km/s|
|Proper motion (μ)||RA: −210.49 mas/yr
Dec.: −138.74 mas/yr
|Parallax (π)||37.55 ± 0.16 mas|
|Distance||86.9 ± 0.4 ly
(26.6 ± 0.1 pc)
|Absolute magnitude (MV)||+0.2|
|Surface gravity (log g)||4.06 ± 0.05 cgs|
|Rotational velocity (v sin i)||236 km/s|
−24 × 106 years
Delta Corvi (δ Crv, δ Corvi) is a star in the southern constellation of Corvus. It has the traditional name Algorab (from Arabic الغراب al-ghuraab, meaning "the crow"). This is a third magnitude star at a distance of 86.9 light-years (26.6 parsecs) from Earth. In 1823, it was found to be a wide double star by British astronomers James South and John Herschel. Since that time, the position of the two stars with respect to each other has not changed.
This star has more than 2.7 times the mass of the Sun, which is causing it to radiate a much higher energy output—roughly 69 times the Sun's luminosity. The effective temperature of the outer atmosphere is 10,400 K, giving it the white hue of an A-type star. The spectrum matches a stellar classification of A0 IV(n) kB9. Although it is only around 260 million years old, the luminosity class of 'IV' indicates this is a subgiant star that has nearly exhausted the supply of hydrogen at its core and is in the process of evolving away from the main sequence of stars like the Sun.
Algorab displays no excess infrared emission that would otherwise suggest the presence of circumstellar matter. It has a magnitude 9.3 companion, HR 4757 B, with a classification of K2Ve at an angular separation of 24.2 arcseconds along a position angle of 214°. Although the two stars share a common proper motion, the significant differences in their estimated ages suggests that they may not be physically connected.
In Chinese, 軫宿 (Zhěn Sù), meaning Chariot (asterism), refers to an asterism consisting of δ Corvi, γ Corvi, ε Corvi and β Corvi. Consequently, δ Corvi itself is known as 軫宿三 (Zhěn Sù sān, English: the Third Star of Chariot.).
USS Algorab (AKA-8) is a United States navy ship.
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