Beta Cephei
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Beta Cephei |
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Observation data Epoch J2000 |
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Constellation (pronunciation) |
Cepheus |
Right ascension | 21h 28m 39.5971s |
Declination | +70° 33' 38.578"' |
Apparent magnitude (V) | 3.216 |
Characteristics | |
Spectral type | B2IIIV |
U-B color index | ? |
B-V color index | ? |
Variable type | Variable Star of beta Cep type |
Astrometry | |
Radial velocity (Rv) | -8.2 km/s |
Proper motion (μ) | RA: 12.60 mas/yr Dec.: 8.73 mas/yr |
Parallax (π) | 5.48 ± 0.47 mas |
Distance | 600 ± 50 ly (180 ± 20 pc) |
Absolute magnitude (MV) | 3.015 |
Details | |
Mass | 12 M☉ |
Radius | ? R☉ |
Luminosity | 14.600 L☉ |
Temperature | ? K |
Metallicity | ? |
Rotation | ? |
Age | ? years |
Other designations | |
FK5 809, SBC7 859, * 8 Cep, GC 30118, ADS 15032 A, GCRV 13520, MCW 989, TD1 28199, AG+70° 738, N30 4748, TYC 4465-2643-1, BD+69 1173, GSC 04465-02643, ALFIRK, HD 205021, PLX 5192, CSI+69° 1173 1, HGAM 1007, 2E 2128.0+7020, HIC 106032, PPM 10863, AAVSO 2127+70, 2E 4480, HIP 106032, ROT 3532, EUVE J2128+70.5, HR 8238, SAO 10057.
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Database references | |
SIMBAD | data |
Beta Cephei (β Cep / β Cephei) is a star in the constellation Cepheus. It also has the traditional name Alfirk (Arabic الفرقة al-firqah), meaning "The Flock" (referring to a flock of sheep).
Beta Cephei is the prototype of the Beta Cephei variable stars. Its magnitude varies between +3.15 and +3.21 with a period of 0.1904844 days. It belongs to the spectral class B2IIIev and is 595 light years from Earth.
[edit] References
- http://jumk.de/astronomie/prototype-stars/beta-cephei.shtml
- HD 205021 -- Variable Star of beta Cep type. SIMBAD Astronomical Database. Retrieved on 2007-03-01.