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Zeta Draconis
Zeta Draconis (ζ Draconis, abbreviated Zet Dra, ζ Dra) is a binary star in the northern circumpolar constellation of Draco. With an apparent visual magnitude of +3.17, it is the fifth-brightest member of this generally faint constellation. Its distance from the Sun has been measured using the parallax technique, yielding an estimate of roughly . The two components are designated Zeta Draconis A (formally named Aldhibah , after the traditional name of the system) and B. Nomenclature ''ζ Draconis'' ( Latinised to ''Zeta Draconis'') is the system's Bayer designation. The designations of the two components as ''Zeta Draconis A'' and ''B'' derives from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). Zeta Draconis has the old Arabic name الذئب ''al-dhiʼb'' "the wolf" or "the hyena", given in its feminine form "Al Dhiʼbah" (ذئبة) in Allen (1899) (though he mis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Draco (constellation)
Draco is a constellation in the far northern sky. Its name is Latin for dragon. It was one of the 48 Lists of constellations, constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations today. The north pole of the ecliptic is in Draco. Draco is circumpolar star, circumpolar from northern latitudes. There it is never setting and therefore can be seen all year. Features Stars Thuban (α Draconis) was the northern pole star from 3942 BC, when it moved farther north than Theta Boötis, until 1793 BC. The Egyptian Pyramids were designed to have one side facing north, with an entrance passage geometrically aligned so that Thuban would be visible at night. Due to the effects of Axial precession (astronomy), precession, it would again be the pole star around the year AD 21000. It is a blue-white giant star of magnitude 3.7, 309 light-years from Earth. The traditional name of Alpha Draconis, Thuban, means "head of the serpent". T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
