Mizar

noun

Mi·​zar ˈmī-ˌzär 

astronomy

: a group of stars of the second magnitude that is located near Alcor in the handle of the Big Dipper

Alcor and Mizar, in the bend of the handle of the Big Dipper, are actually a complex system. Alcor is a binary and Mizar is a quadruple system of two binary stars. Keen eyes can usually split Alcor and Mizar into individual stars, but you'll need a telescope to resolve the other companions.

—Becky Ramotowski, San Antonio Express-News, 21 June 2011

called also Zeta Ursae Majoris

Note: Although historically called a star, what we know as Mizar is actually a set of four separate stars, tightly bound together in two pairs by gravity.

Word History

First Known Use

1812, in the meaning defined above

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