Alcor

Definition

Astronomy

  • star in Ursa Major with a faint companion, Mizar, which can just be distinguished with the naked eye. Spectra of Mizar show that it in turn is also a double star. The two components of Mizar are a genuine double in orbit around each other while Alcor is not part of the system, but is merely aligned with Mizar in the sky as seen from Earth.
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