Epsilon Đại Hùng

Epsilon Ursae Majoris, called Alioth, is the brightest star of the constellation Ursa Major, appearing at apparent magnitude 1.76. A white A-type star, it carries a nearly neutral B–V index of −0.022 and lies 82.5 light-years from Earth. Its absolute magnitude of −0.26 indicates an intrinsic luminosity above the Sun's. Positioned at a far-northern declination of +55°, Alioth is circumpolar across much of the northern hemisphere and never sets. It sits closest to the bowl among the three stars that trace the handle of the familiar Plough asterism, making it a well-known signpost of the northern sky.