Eta Ursae Majoris (Eta UMa, η Ursae Majoris, η UMa) is a star in the constellation Ursa Major. It has the traditional names Alkaid (or Elkeid) and Benetnash (Benetnasch). Alkaid is the most eastern (leftmost) star in the Big Dipper (Plough) asterism. However, unlike most stars of the Big Dipper, it is not a member of the Ursa Major moving group. With an apparent visual magnitude of +1.84, it is the third brightest star in the constellation and one of the brightest stars in the night sky.
This is a 10 million year old B-type main sequence star with a stellar classification of B3 V. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. It has six times the mass of the Sun and 3.4 times the Sun's radius. Eta Ursae Majoris is radiating around 1,350 times as much luminosity as the Sun from its outer atmosphere at an effective temperature of about 16,823 K, giving it the blue-white hue of a B-type star. This star is an X-ray emitter with a luminosity of 9.3 × 1028 erg s–1.
Alkaid in Space Opera
In the game Escape Velocity the system has on uninhabited planet with the same name as the system and one inhabited moon, Alkaidion.
On the net: Wikipedia, Ashland Astro,