Thousands of years ago, people spent hours gazing at the night sky. They found that by connecting the stars as if they were dots, patterns emerged that resembled animals, people and things.
Today, we call star patterns constellations. Eventually, 88 star patterns were identified. The patterns helped people navigate on land and by sea as well as tell time, appearing in different parts of the sky depending on the day and year. (The stars don't move. Earth moves, rotating on its axis once every 24 hours and revolving around the Sun once every year.)
Do you enjoy stargazing? Here's help finding the different stars and constellations. (You can also reference star maps on our astronomy links page.)
The Big Dipper
The big dipper is not a constellation, but an asterism (a familiar group of stars located within a constellation). See image to the left (photo credit: NASA/Jerry Lodriguss).
Look for seven major stars: four in the "bowl" and three in the "handle." The two stars on the outside of the bowl are called the "pointer" stars. They point to Polaris, a bright star that is also called the North Star because with it you can figure out which way is north.
To find north:
- Find the Big Dipper.
- Find the pointer stars.
- Find Polaris.
- Look straight up.
- Turn your body towards Polaris.
- Now, you're facing north.
Ursa Major, the Great Bear
If you find the Big Dipper, you have found the Great Bear: The Dipper's handle is the Bear's tail. See the image to the right (credit: NASA/Akira Fujii).
Legends about the Great Bear abound. Ancient Greeks and Romans believed that a mythological king grabbed its tail, swung it around, and swung it into the sky to whirl around the North Pole forever. Some Native Americans believed that the three tail stars were hunters chasing the Bear.
Ursa Minor, the Little Bear
Polaris will help you find the Little Dipper, also known as Ursa Minor, or the Little Bear. Polar is the star on the end of the Little Dipper's handle.
Orion, the Hunter
This is easiest to find in the winter. Look for three bright stars in a line—these are Orion's belt. See image to the left (credit: NASA).
The two stars north of this are Orion's shoulders. One of these is Betelgeuse ("BEETLE-juice"), which is a giant red star. The two brighter stars to the south are his legs.
Ancient people used Orion to predict the seasons: If it appeared at midnight, the grapes were ready to harvest. If it appeared in the morning, summer was beginning. If it appeared in the evening, winter had arrived.
Canis Major, the Great Dog
This is named for the larger of Orion's two hunting dogs (the other, Canis Minor, has only two stars).
To find Canis Major:
- Imagine a straight line through Orion's belt.
- Move your eyes left (south) until you come to a very bright star—that's Sirius, the nose of the dog.
- Look farther south to find a triangle of stars that marks the dog's hindquarters.
Ancient Egyptians called Sirus "the Nile Star" because it always appeared in the sky right before summer began and the waters of the River Nile began to flood. In medieval Europe, people thought that a combination of light from the Sun and Sirius caused the hot and humid "dog days" of summer.
On a clear and moonless night away from bright lights, you can see about 2,500 stars. Spend some time looking at the sky and connect the stars!