Zeta Aquilae
double star in the equatorial constellation of Aquila
Zeta Aquilae is a binary star system in the equatorial constellation of Aquila. Its name is a Bayer designation that is Latinized from ζ Aquilae, and abbreviated Zeta Aql or ζ Aql. This system is readily visible with the naked eye as a point of light, having a combined apparent visual magnitude of 2.983. Based on parallax measurements obtained during the Hipparcos mission, it is approximately 83 light-years (25 parsecs) distant from the Sun. It is a candidate member of the TW Hydrae association of co-moving stars.
Zeta Aquilae's two components can be designated Zeta Aquilae A and B. The former is officially named Okab, pronounced , the traditional name for the system. Zeta Aquilae has a number of companions listed and together they are designated WDS J19054+1352. As the primary star of this group, Zeta Aquilae also bears the designation WDS J19054+1352A. The companions are then designated WDS J19054+1352B, C, D and E.
Nomenclature
ζ Aquilae, Latinised to Zeta Aquilae, is the binary's Bayer designation. The designations of the two components as Zeta Aquilae A and B derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). WDS J19054+1352 is the entry of the wider system of which Zeta Aquilae is a member in the Washington Double Star Catalog.
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This entry incorporates text from “Zeta Aquilae” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.