Omicron Persei


Omicron Persei is a triple star system in the constellation of Perseus. From parallax measurements taken during the Hipparcos mission it is approximately 1,100 light-years from the Sun.
The system consists of a binary pair designated Omicron Persei A and a third companion Omicron Persei B. A's two components are themselves designated Omicron Persei Aa and Ab.

Nomenclature

ο Persei is the system's Bayer designation. The designations of the two constituents as Omicron Persei A and B, and those of A's components - Omicron Persei Aa and Ab - derive from the convention used by the Washington Multiplicity Catalog for multiple star systems, and adopted by the International Astronomical Union.
It bore the traditional name Atik, Arabic for "the shoulder". Some sources, including a planetarium software package, an atlas, and a web site attribute the name Atik to the nearby, brighter star Zeta Persei. In 2016, the International Astronomical Union organized a Working Group on Star Names to catalogue and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems. It approved the name Atik for the component Omicron Persei A on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.
In Chinese, 卷舌, meaning Rolled Tongue, refers to an asterism consisting of Omicron Persei, Nu Persei, Epsilon Persei, Xi Persei, Zeta Persei and 40 Persei. Consequently, the Chinese name for Omicron Persei itself is 卷舌五, "the Fifth Star of Rolled Tongue".

Namesake

was a ship of the United States Navy.

Properties

Omicron Persei A is a spectroscopic binary consisting of a spectral type B1 giant and a type B2 dwarf orbiting each other every 4.4 days. Omicron Persei lies just north of the open cluster IC 348, but is not catalogued as a member. Both IC 348 and Omicron Persei belong to the Perseus OB2 association.