Magnitude 4.35 Constellation Ursa Minor | Rotation 19 hours Apparent magnitude (V) 4.35 | |
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Similar Gamma Ursae Minoris, Beta Ursae Minoris, Epsilon Ursae Minoris, Iota Draconis, Mu Ursae Majoris | ||
Delta Ursae Minoris (δ Ursae Minoris, abbreviated Delta UMi, δ UMi), also named Yildun, is a star in the constellation of Ursa Minor.
Delta Ursae Minoris is a white A-type main sequence dwarf with an apparent magnitude of +4.35 approximately 172 light years from the Sun.
Nomenclature
δ Ursae Minoris (Latinised to Delta Ursae Minoris) is the star's Bayer designation.
It bore the traditional name Yildun (also spelled Vildiur, Jildun, Gildun, and Yilduz) from the Turkish yıldız "star". It may also have been called Pherkard, an alternate spelling of Pherkad, used for Gamma Ursae Minoris and 11 Ursae Minoris. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name Yildun for this star on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names.