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Triangulum Australe
Corona Borealis
Ursa Minor looks like a slightly stretched out, and much dimmer version, of its "big brother" Ursa Major. The interesting part of Ursa Minor is its brightest star at the end of the "tail" which is of course Alpha Ursae Minoris, but is also called Polaris or the North Star. The Earth's axis happens to point almost exactly towards Polaris. The exact location which the Earth's axis points towards in the north is called the north celestial pole.
The skies are painted with unnumb'red sparks,
They are all fire and every one doth shine;
But there's but one in all doth hold his place.
Julius Ceaser III i 63-65
When Shakespeare compared Julius Ceaser to a star that "doth hold his place" he was referring to Polaris. All the other stars trace a circle around Polaris once every 23 hours, 56 minutes and 4 seconds while Polaris stays fixed in its position in the sky. Imagine yourself standing at the North Pole. Polaris would be directly overhead while all the other stars would be tracing concentric circles around it. If the horizon is clear, you could see a star travel along it. Now travel south. As you travel south, Polaris will gradually dip towards the horizon. The other stars will continue to trace circles around Polaris, but because Polaris is no longer directly overhead, that star which was originally at the horizon will both dip below and raise above the horizon as it travels around Polaris.
The farther you travel south, the lower Polaris will appear in the sky, until you finally reach the equator where Polaris will appear just on the northern horizon. The elevation of Polaris indicates the latitude of the observer, which is why sailors were able to accurately determine their latitude centuries before being able to determine their longitude.
Latitude and longitude is used to determine our position on the Earth. A similar system is used to determine the position of a star in the sky. The celestial equivalent of latitude (north south) is called declination.
The imaginary circles around Polaris determine a star's declination. Polaris itself is located at 90 degrees declination. The bright stars of the northerly Big Dipper are located between 50 and 60 degrees declination while the Southern Cross is around minus 50-60 degrees declination. If you look at the map displayed above you can see the lines of declination displayed for every 10 degrees.
Everything written above also applies to the south except that there is no conveniently bright star like Polaris at the south celestial pole.
One final point. There is nothing special about the north or south celestial poles other than the Earth's axis happens to point there. Furthermore, the Earth's axis does a slow "wobble" every 25,800 years, which is officially called "the Precession of the Equinoxes". The position of the celestial poles slowly changes because of the wobble and Polaris will not remain the "North Star" forever.