Alpha Corvi (α Corvi, abbreviated Alpha Crv, α Crv), also named Alchiba /ˈælkɪbə/,[12] is an F-type main-sequence star and, despite its "alpha" designation, is the fifth-brightest star in the constellation of Corvus. Based on parallax measurements made by the Gaia mission, it is approximately 49 light-years from the Sun.[1]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Corvus |
| Right ascension | 12h 08m 24.81727s[1] |
| Declination | −24° 43′ 43.9521″[1] |
| Apparent magnitude (V) | 4.03[2] |
| Characteristics | |
| Spectral type | F1 V[3] + M4 V[4] |
| U−B color index | +0.00[2] |
| B−V color index | +0.34[2] |
| Variable type | Gamma Doradus?[5] |
| Astrometry | |
| Radial velocity (Rv) | +3.0[6] km/s |
| Proper motion (μ) | RA: +96.976 mas/yr[1] Dec.: −40.023 mas/yr[1] |
| Parallax (π) | 66.7696 ± 0.1804 mas[1] |
| Distance | 48.8 ± 0.1 ly (14.98 ± 0.04 pc) |
| Absolute magnitude (MV) | 3.25[7] |
| Details | |
| Mass | 1.32[8] M☉ |
| Radius | 1.373[9] R☉ |
| Luminosity | 4.145[9] L☉ |
| Surface gravity (log g) | 4.27[8] cgs |
| Temperature | 7,035[9] K |
| Metallicity [Fe/H] | −0.04[8] dex |
| Rotational velocity (v sin i) | 16.9 ± 1.5[10] km/s |
| Age | 1.2–1.58[8] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Nomenclature
α Corvi (Latinised to Alpha Corvi) is the star's Bayer designation.
It bore the traditional names Al Chiba (Arabic: ألخبا al-xibā, 'tent') and Al Minliar al Ghurab (Arabic منقار الغراب al-manxar al-ghurab)[13] or Minkar al Ghurab. The latter appeared in the catalogue of stars in the Calendarium of Al Achsasi al Mouakket, which was translated into Latin as Rostrum Corvi, 'beak of the crow'.[14] In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[15] to catalogue and standardize proper names for stars. The WGSN approved the name Alchiba for this star on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.[12]
In Chinese astronomy, Alchiba is called 右轄, Pinyin: yòuxiá, meaning 'right linchpin', because it stands alone in the 'right linchpin' asterism, Chariot mansion (see: Chinese constellations),[16] 右轄, yòuxiá was westernized into Yew Hea by R.H. Allen.[13]
Namesake
USS Alchiba (AKA-6) is a former United States Navy ship.
Properties
Alchiba has a spectral class F1V,[3] classifying it as a main sequence star fusing hydrogen into helium at its core. This star exhibits periodic changes in its spectrum over a three-day period, which suggests it is either a spectroscopic binary or (more likely) a pulsating Gamma Doradus-type variable.[5] Alchiba has 32% more mass[8] and is 37% larger than the Sun. It is four times more luminous and has a surface effective temperature of 7,035 K,[9] giving it the yellow-white hue of an F-type star. The abundance of chemical elements other than hydrogen and helium, what astronomers name metallicity, is slightly lower than that of the Sun.[8]
Alpha Corvi has a common proper motion companion, named Alpha Corvi B (or Alchiba B), located about 3.1 arcsec away. It is a red dwarf with a spectral type of M4V.[4]
See also
References
External links
- Alpha Corvi by Professor Jim Kaler.