Dubhe
α Ursae Majoris
Location of α Ursae Majoris (circled)
Observation data Epoch J2000 Equinox J2000
Constellation
Ursa Major
Right ascension
11h 03m 43.67152s
Declination
+61° 45′ 03.7249″
Apparent magnitude (V)
1.79
Characteristics
Spectral type
K0III + F0V
U−B color index
+0.93
B−V color index
+1.07
Variable type
Suspected
Astrometry Radial velocity (Rv ) −9.4± 0.3 km/sProper motion (μ) RA: –134.11 mas /yr Dec.: –34.70 mas /yr Parallax (π) 26.54 ± 0.48 mas Distance 123 ± 2 ly (37.7 ± 0.7 pc ) Absolute magnitude (MV ) −1.10± 0.04
Details α UMa A Mass 3.44± 0.11 M ☉ Radius 17.03± 0.13 R ☉ Luminosity 165.1± 8.3 L ☉ Surface gravity (log g ) 2.20 cgs Temperature 5,012± 65 K Metallicity [Fe/H] −0.20± 0.07 dex Rotational velocity (v sin i ) 2.6± 1.0 km/sAge 280± 30 Myr α UMa B Mass ~1.6 M ☉
Other designations Dubhe, Ak,
α Ursae Majoris, α UMa, Alpha UMa ,
50 UMa ,
NSV 5070,
BD +62°1161,
FK5 417,
GC 15185,
HD 95689,
HIP 54061,
HR 4301,
SAO 15384,
PPM 17705,
ADS 8035,
CCDM J11037+6145AB,
WDS J11037+6145AB
Database references SIMBAD data
Dubhe or Alpha Ursae Majoris is a red giant star in the constellation of Ursa Major . It is 27 times wider than the Sun .
References
1 2 3 4 5 van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics . 474 (2): 653– 664. arXiv :0708.1752 . Bibcode :2007A& A...474..653V . doi :10.1051/0004-6361:20078357 . S2CID 18759600 .
1 2 3 Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory , 4 (99): 99, Bibcode :1966CoLPL...4...99J
1 2 Guenther, D. B.; et al. (2000). "Evolutionary Model and Oscillation Frequencies for α Ursae Majoris: A Comparison with Observations" . The Astrophysical Journal . 530 (1): L45– L48. Bibcode :2000ApJ...530L..45G . doi :10.1086/312473 . PMID 10642202 .
↑ Tokovinin, A. A. (1997). "MSC - a catalogue of physical multiple stars" . Astronomy and Astrophysics Supplement Series . 124 : 75– 84. Bibcode :1997A& AS..124...75T . doi :10.1051/aas:1997181 .
↑ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S . 1 . Bibcode :2009yCat....102025S .
↑ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters . 32 (11): 759– 771. arXiv :1606.08053 . Bibcode :2006AstL...32..759G . doi :10.1134/S1063773706110065 . S2CID 119231169 .
1 2 Carney, Bruce W.; et al. (March 2008), "Rotation and Macroturbulence in Metal-Poor Field Red Giant and Red Horizontal Branch Stars", The Astronomical Journal , 135 (3): 892– 906, arXiv :0711.4984 , Bibcode :2008AJ....135..892C , doi :10.1088/0004-6256/135/3/892 , S2CID 2756572
↑ Baines, E.; et al. (2017). "Fundamental Parameters of 87 Stars from the Navy Precision Optical Interferometer" . The Astronomical Journal . 155 (1): 30. arXiv :1712.08109 . Bibcode :2018AJ....155...30B . doi :10.3847/1538-3881/aa9d8b . S2CID 119427037 .
↑ McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances", Astrophysical Journal Supplement Series , 74 : 1075– 1128, Bibcode :1990ApJS...74.1075M , doi :10.1086/191527
↑ "DUBHE -- Spectroscopic binary" , SIMBAD , Centre de Données astronomiques de Strasbourg , retrieved 2011-12-23