The Big Dipper
|Constellation tour in Spring
|Date & Time: ||Jan 1 2000, 25:29 JST(+0900), 25min. Exp.
|Optical: ||SMC TAKUMAR f=105mm F2.4, Aperture: F4.0, with Cokin Diffuser-1 filter
|Auto-guided with TAKAHASHI EM-200 Equatorial
|Camera: ||PENTAX 67
|Film: ||Ektachrome E200 (+1EV pushed)
|Location: ||Kita-ibaraki city, Ibaraki pref.
Although it's not a formal constellation, this picture shows you a very noticeable seven stars of "The Big Dipper".
The asterism forms the lower part of the body and tail of Big Bear, Ursa Major.
The Big Dipper is very famous as a "polestar finder", we can find the Polaris by stretching five times a line of two stars at the tip of dipper.
And the Mizar, the second star from the tip of handle, is a well-known double star with a 5th magnitude star of Alcor, detectable only with naked eyes.
The Big Dipper can be found very easily in northern sky, so it had been connected with various things in all over the ancient world.
In china, they had seen the asterism as an ox-drawn carriage of the emperor, American Indians had regarded it as a big bear same with the ancient Greeks, and so on.
In case of Japan, though "Hokuto-shichisei (the northern seven stars of dipper)" is most general,
there were many other names of "the stars of seven week days", "the stars of rudder", etc...