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Alpha Draconis

Astronomy Alpha CygniAlpha Equulei

[3445] alpha Draconis or Thuban ("the basilisk") is not a very conspicuous star in comparison. It is a binary star consisting of a white giant with an apparent magnitude of 3.

 


Thuban = Alpha Draconis
Rastaban = Beta Draconis
Eltanin = Gamma Draconis
Altais (Nodus II) = Delta Draconis
Al Dhibain "Posterior" = Zeta Draconis
Al Dhibain "Prior" = Eta Draconis
Theta Dra = Theta Draconis
Edasich = Iota Draconis # ...

Thuban (alpha Draconis) is the brightest star in the constellation Draco; it is located in the dragon's tail. Thuban means "dragon or serpent" in Arabic. Thuban was the Earth's pole star about 5,000 years ago.

In fact Thuban (alpha Draconis) was once the Pole Star, at about the time these stories were being told for the first time. A very old and extensive constellation, Draco once held even more stars.

Even though Thuban carries the Bayer designation Alpha Draconis, at apparent magnitude 3.65 it is over a magnitude fainter than the brightest star in the constellation, γ Dra (Etamin), whose apparent magnitude is 2.23.

Alpha Draconis is called Thuban, from a highly corrupted form of the Arabic ra's al-tinnin, ‘the serpent's head'. Beta Draconis is called Rastaban, another corrupted form of the same Arabic name.

the North Star was a star called Thuban (also known as Alpha Draconis), and in about 13,000 years from now the precession of the rotation axis will mean that the bright star Vega will be the North Star.

Thabit Upsilon Orionis
Theemin Upsilon-2 Eridani
Thuban Alpha Draconis
Tien Kuan Zeta Tauri
Toliman Alpha Centauri
Torcularis Septentrionalis Omicron Piscium
Tseen Kee Phi Velorum
Tureis Pi Puppis
Tyl Epsilon Draconis ...

The ancient Egyptians regarded as pole star the star Thuban or "Alpha Draconis," the brightest star (=alpha) in the constellation Draco, the serpent. For more information about the motion of the pole, see here and here.

The star lies in the southeastern part (15:24:55.8+58:57:57.8, ICRS 2000.0) of Constellation Draco (see chart and photo), the Dragon -- west of Theta Draconis, southeast of Thuban (Alpha Draconis), and south of the Big Dipper (or Plough).

See also: Sky, Star, Thuban, Draco, Constellation