This section provides a brief introduction of the north star, or the pole, Polaris.
Polaris, more commonly known as The North Star, North Star, or Pole Star,
is the closest star to the North Celestial Pole.
The following picture provides you a good illustration, http://www.lpi.usra.edu:
Polaris has been used as the navigation star for centuries in Northern Hemisphere.
From an observer point of view, Polaris hangs in the north direction above the horizon
as an angle approximately equal to the degree of latitude of the observer.
This means that:
If you are standing on the Equator, Polaris will be seen on the horizon in the north direction.
If you are standing on the North Pole, Polaris will be seen directly overhead.
If you are standing on a latitude of 30 degrees, Polaris will be seen 30 degrees off the horizon in the north direction.
Another way to find Polaris by following the line traced from Merak to Dubhe,
also known as the Pointers, the two stars at the end of the bowl of the Big Dipper, or Ursa Major, the Great Bear.
The following picture provides you a good illustration, http://www.indepthinfo.com:
Polaris stands almost motionless on the sky, and all the stars of the Northern sky appear to rotate around it.
Below is a nice picture of the night sky above Hawaii was taken by leaving the camera shutter open for a long time,
by Richard J. Wainscoat, http://www.wainscoat.com/astronomy.
The picture captures the apparent movement of the stars caused by Earth's rotation on its axis.
Polaris is the star in the center of the star field; it shows essentially no movement.
Earth's axis points almost directly to Polaris, so this star is observed to show the least movement.
The other stars appear to trace arcs of movement because of Earth's spin on its axis.
Polaris is part of a minor constellation called Little Dipper, Little Bear, or Ursa Minor.
Polaris is the last star on the handle of Little Dipper, or the last star of the tail of Little Bear.
In Chinese culture, Polaris is called Bei Ji Xing (北极星).
Big Dipper is called Bei Dou Xing (北斗星).
