Constellation - A constellation is a group of stars that form an imaginary pattern.
Zodiac Constellations - The constellations of the zodiac are those groups of stars that travel directly overhead, following the same path as our Sun. Examples of the zodiac constellations are Taurus the Bull, Leo the Lion and Scorpius the Scorpion.
Other Constellations to Learn are Crux the Southern Cross, Centaurus the Centaur, and Orion the Hunter.
The Bayer Designation of Naming Stars - Stars in constellations are named according to their brightness. The brightest star in a constellation is called the Alpha star, the second brightest star is called the Beta star, and so on using the letters of the Greek alphabet.
For example, in the constellation Crux (the Southern Cross), the stars in order of brightness are Alpha Crucis, Beta Crucis, Gamma Crucis, Delta Crucis and Epsilon Crucis. Also, the Pointers that point to the Southern Cross are part of the constellation Centaurus the Centaur. The brightest star of the 2 Pointers is called Alpha Centauri and the second brightest is called Beta Centauri.
Positions & Movements of Stars
Positions of Stars
Elevation - the number of degrees a star is above the horizon
Azimuth - the number of degrees a star is along the horizon
Movement of our Sun - Our Sun, which is a star, appears to move across the sky from east to west. It appears to move directly overhead along a path called the zenith. This apparent motion is because the Earth is actually rotating in the opposite direction from west to east.
Movement of Stars - In the northern hemisphere, stars appear to rotate around a central point in the sky called the North Celestial Pole where the Pole Star is. The North Celestial Pole is directly above the North Pole. In the southern hemisphere, stars appear to rotate around an imaginary point in the sky called the South Celestial Pole. The South Celestial Pole is directly above the South Pole.
