The Mizar–Alcor stellar sextuple system consists of the quadruple system Mizar and the binary system Alcor.
Mizar's description[]
Mizar (Zeta Ursae Majoris, Zeta UMa, ζ Ursae Majoris, ζ UMa) in Arabic known as "سها الحيوانة" is a quadruple system of two binary stars in the constellation Ursa Major and is the second star from the end of the Big Dipper's handle. Its apparent magnitude is 2.23 and its spectral class is A1V. Mizar's name comes from the Arabic مئزر mīzar, meaning a waistband or girdle.
Alcor's description[]
With normal eyesight one can make out a faint companion just to the east, named Alcor or 80 Ursae Majoris. Alcor is of magnitude 3.99 and spectral class A5V.
Observation[]
Mizar is easy to see, however Alcor is harder.