What is a Constellation?
A constellation is a group of stars that form a pattern named after its form or identified with a mythological figure. There are 88 official constellations. You can also see different constellations from the Northern and Southern Hemisphere.
What are some of the Constellations and How did They get Their Names?
Some of the constellations are Ursa Major, which The Big Dipper is part of, The Little Dipper, Aquarius, Pegasus, Scorpius, Hercules, Orion, etc. Constellations get their names by ancient astronomers after the things they thought the star patterns looked like, for example, a lion (Leo) or a swan (Cygnus), or a character that was in their myths such as Hercules.
What are Constellations used for?
Throughout history, constellations were used for many different things, the first use for them was probably for religious reasons, many cultures believed that the positions of the stars were their God's way of telling stories. A more practical use for constellations was agriculture, before there were calendars, people had no way of determining when to harvest, except by the stars. Constellations helped with navigation, it's fairly easy to find the North Star once you find the Little Dipper.
Why Do We See Different Constellations During the Year?
Throughout the year, constellations gradually shift to the west, it's caused by Earth's orbit around the Sun. In the Summer, people are looking in a different direction in space at night than they are during the winter.
What is the Zodiac?
From Earth, the Sun appears to trace a circular path defines the plane of the ecliptic. The zodiac the group of constellations that fall along the plane of the ecliptic. It is through these constellations that our Sun appears to "pass" during the year. The annual cycle of the zodiac was used by ancient cultures to determine the time of year.