Big Dipper and Little Dipper

The Big Dipper and Little Dipper are some of the most easily recognized groups of stars in the night sky. The Big Dipper is positioned (and easily detected) in a distinct group of stars. A group of stars is called an asterism. An asterism typically has a popular name but is smaller than a constellation.

The Big Dipper is located within an asterism inside the Ursa Major Constellation, while the Little Dipper resides in the neighboring Ursa Minor Constellation. The two sky bears and the dippers are close to each other and are relatively easy to pick out from the sky’s myriad of stars.

Asterisms, Not Constellations

The Big and Little Dippers are actually not constellations; instead, they are asterisms. That’s a noticeable star pattern outside the International Astronomical Union’s 88 recognized constellations.

The Big Dipper outlines the Greater Bear’s tail and hindquarters, while the Little Dipper also rounds out the Little Bear’s backside. Polaris lies at the tip of Ursa Minor’s tail.

Polaris: Connecting the Dippers

The North Star, Polaris, sits above the North celestial pole and is easy to find once you locate the Big Dipper. The two “pointer” stars at the cup’s edge, Merak and Dubhe, point toward Polaris, the star at the tip of the Little Dipper’s handle. It is also the end of the little bear’s tail in the Ursa Minor Constellation.

So Polaris is part of the connection between the two dippers, and once you find it, you’re pointing North. And that helps you get your bearings in all your sky observations.

The Big Dipper has bright stars and is one of the most prominent night sky groupings. But the Little Dipper has faint stars, which are often hard to see except for Polaris.

Connecting the Dippers — Polaris at the Center, Image: NASA and Preston Dyches

Double Star In The Big Dipper

The Big Dipper is probably the most familiar star grouping, which makes it excellent for finding your way around celestial objects. But the asterism holds an incredible surprise within its handle. One of the stars is actually two stars. But when you look even closer, you’ll see that the two are really six stars!

Mizar and Alcor are about halfway down the Big Dipper’s handle. And you can see with your eyes or through a pair of binoculars that they are separate stars. You usually need a telescope to see a double star’s separate entities. So seeing these two Big Dipper stars with your own eyes is a treat.

But it gets even better because the two stars aren’t what they seem. They’re actually six stars! Mizar is two pairs of binary stars, and Alcor is one binary star pair. So what you first see as one star becomes six.

Double Star In The Big Dipper — Image: NASA and Yuri Beletsky, Carnegie Las Campanas Observatory and TWAN

Folk Tales Of The Big And Little Dipper

Mi’kmaq First Nations (Canada)

The First Nation tribe of the Mi’kmaq people called the Big Dipper’s constellation the Bear. They also referred to the Corona Borealis as the Bear’s Cave. Legend has it that when the Bear awakes from hibernation in the Cave, the seven sky birds start hunting it.

The sky birds are three stars in the Big Dipper’s handle and four stars from Bootes, representing different bird species on Earth. The story explains the Bear’s life cycle of the birds capturing, killing, and cooking it.

Then the Great Bear’s spirit enters another bear who is sleeping in the Bear Cave. And ultimately, that new Bear represents the Winter, Spring, and Summer cycles of the Bear’s (Big Dipper’s) position in the sky.

Folk Tales Of The Big And Little Dipper — Image: Alder Planetarium

Ursa Major: Greek Mythology

Like all good stories, the Big Dipper’s origin is full of love and revenge. Zeus fell in love with and impregnated a maiden, Callisto. After the child’s birth, Zeus’ wife, Hera, turned the new mother into a bear. Callisto wandered through the forest as a bear for years until she came upon her son. Arcas raised his spear toward the bear, but Zeus sent both mother and son into the heavens.

And now Callisto reigns as Ursa Major and the Big Dipper, while her son, Arcas, lives as Ursa Minor, the Little Dipper. But Hera hated seeing them in the sky, so she plotted with the sea gods. Together they banned the Bear from swimming in the ocean, and now the constellations continually travel the sky throughout the Northern Hemisphere seasons.

Stars In The Big Dipper

Both asterisms contain seven stars each. And while Polaris is the most prominent in the Little Dipper, the pointers Dubhe and Merak are likely the most well-known in the Big Dipper. Here are the stars in the Big Dipper.

Alkaid or Alcor (binary pair) or Eta Ursae Majoris
Mizar (two binary pairs) or Zeta Ursae Majoris
Alioth or Epsilon Ursae Majoris
Megrez or Delta Ursae Majoris
Phecda or Gamma Ursae Majoris
Dubhe (pointer) or Alpha Ursae Majoris
Merak (pointer) or Beta Ursae Majoris

Stars In The Little Dipper

Polaris, the North Star, is the most famous star in the Little Dipper. Its official name is Alpha Ursae Minoris, the 48th brightest star. The North Star represents true north, so navigating by it keeps followers on a straight path.

The remaining stars in The Little Dipper follow.

Kochab (pole guardian) or Beta Ursae Minoris
Yildun or Delta Urase Minoris
Pherkad (pole guardian) or Gamma Ursae Minoris
Zeta Ursae Minoris
Eta Ursae Minoris
Epsilon Ursae Minoris

Eta Ursae Minoris is the faintest of the Little Dipper stars at a magnitude of 4.95. So it is difficult to see if you’re in a light-polluted location.

Location Of The Asterisms

The Big Dipper and the Little One reside in the Northern Hemisphere, so they are almost impossible to see from the Southern Hemisphere. They are endless night sky features for us in the north, visible year-round. Polaris stays in the same position, while the other stars look like they rotate around it.

The Big Dipper is much more visible even from light-polluted cities, but you need dark skies to see the Little Dipper. Polaris is relatively easy to spot, especially when you look from the Big Dipper to it, but the other stars are very faint.