Stars of northern skies

When you look at the northern sky, you look away from the densely populated galactic centre, so the northern sky generally appears less bright than the southern sky. Among the best-known bright than the northern sky are the constellations urea major and Orion. Some ancient civilization believed that the stars were fixed to a celestial sphere surrounding the earth, and modern maps of the sky are based on a similar idea.

The north and south poles of this imaginary celestial sphere are directly above the north and south poles of the earth, at the points where the earth’s axis of rotation intersects the sphere. The celestial north pole is at the centre of the map shown here, and Polaris lies very close to it.