Alkaid
star in the constellation Ursa Major / From Wikipedia, the free encyclopedia
Alkaid or Eta Ursae Majoris is a white star in the Ursa Major constellation.
Quick Facts Observation data Epoch J2000 Equinox J2000, Constellation ...
Observation data Epoch J2000 Equinox J2000 | |
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Constellation | Ursa Major |
Right ascension | 13h 47m 32.43776s[1] |
Declination | +49° 18′ 47.7602″[1] |
Apparent magnitude (V) | +1.86[2] |
Characteristics | |
Spectral type | B3 V[3] |
U−B color index | –0.68[2] |
B−V color index | –0.19[2] |
Astrometry | |
Radial velocity (Rv) | –10.9[4] km/s |
Proper motion (μ) | RA: –121.17[1] mas/yr Dec.: –14.91[1] mas/yr |
Parallax (π) | 31.38 ± 0.24[1] mas |
Distance | 103.9 ± 0.8 ly (31.9 ± 0.2 pc) |
Absolute magnitude (MV) | −0.67[5] |
Details | |
Mass | 6.1 ± 0.1[6] M☉ |
Radius | 3.4[7] R☉ |
Luminosity | 594 ± 31[8] L☉ |
Surface gravity (log g) | 3.78[8] cgs |
Temperature | 15,540 ± 1157[8] K |
Rotational velocity (v sin i) | 150[9] km/s |
Age | 10.0 ± 2.6[6] Myr |
Other designations | |
Database references | |
SIMBAD | data |
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