by Anthony Ayiomamitis
One of the most beautiful multiple star systems is Mizar (zeta UMa / ζ-UMa) which shines at mag 2.22 with neighbouring Alcor shining at 3.99. This bright star has a luminosity 60.2 times that of the Sun and is approximately 78.2 light-years away. Technical Details: Date: Nov 20, 2009 @ 04:20 - 05:05 UT+2 Location: Athens, Greece (38.2997° N, 23.7430° E) Equipment: AP 160/f7.5 Starfire EDF, AP 1200GTO GEM, SBIG ST-2000XM, SBIG CFW-8A, SBIG LRGB + IR-block Integrations: LRGB @ 10:10:10:10 using 1-/2-min subs, Binning: 1x1, Image Scale: 1.27" per pixel, +0.0° C Further Details: http://www.perseus.gr/Astro-Star-Brightest-UMa-Zeta.htm