Dubhe - α Ursae Majoris (alpha Ursae Majoris)
Dubhe, also designated as α Ursae Majoris (alpha Ursae Majoris), is a variable and double hypergiant star in the constellation of Ursa Major.
Dubhe visual magnitude is 1.79, making it the 33th brightest star in the sky. Thanks to its high brightness, Dubhe is clearly visible when observed from locations with dark skyes, and should be also quite easily visible from light polluted areas.
The table below summarizes the key facts about Dubhe:
Celestial coordinates and finder chart of Dubhe
Dubhe is situated close to the northern celestial pole and, as such, it is visible for most part of the year from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of Dubhe are provided in the following table:
The simplified sky map below shows the position of Dubhe in the sky:
Visibility of Dubhe from your location
Dubhe - α Ursae Majoris (alpha Ursae Majoris) is circumpolar and transits at 13:29 UTC (altitude: 79.7°)
Digitized Sky Survey image of Dubhe
The image below is a photograph of Dubhe from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of Dubhe is -0.119 arcsec per year in Right Ascension and -0.067 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.
Distance of Dubhe from the Sun and relative movement
Dubhe is distant 123.58 light years from the Sun and it is moving towards the Sun at the speed of 9 kilometers per second.
Spectral properties of Dubhe
Dubhe belongs to spectral class K0 and has a luminosity class of III corresponding to a hypergiant star.
The red dot in the diagram below shows where Dubhe is situated in the Hertzsprung–Russell diagram.
Dubhe star system properties
Dubhe is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the Dubhe double sysyem: