Ursa Major facts for kids

Kids Encyclopedia Facts

This page is about the constellation. For the pattern of stars (asterism), see Big Dipper. For other uses, see Ursa Major (disambiguation).

Quick facts for kids
Ursa Major
Constellation
List of stars in Ursa Major
Abbreviation	UMa
Genitive	Ursae Majoris
Pronunciation	ur-SƏ-_-MAY-jər, genitive UR-see-_-mə-JOR-iss
Symbolism	the Great Bear
Right ascension	10.67^h
Declination	+55.38°
Quadrant	NQ2
Area	1280 sq. deg. (3rd)
Main stars	7, 20
Bayer/Flamsteed stars	93
Stars with planets	21
Stars brighter than 3.00^m	7
Stars within 10.00 pc (32.62 ly)	8
Brightest star	Alioth (ε UMa) (1.76^m)
Messier objects	7
Meteor showers	Alpha Ursae Majorids Kappa Ursae Majorids October Ursae Majorids
Bordering constellations	Draco Camelopardalis Lynx Leo Minor Leo Coma Berenices Canes Venatici Boötes
Visible at latitudes between +90° and −30°. Best visible at 21:00 (9 p.m.) during the month of April. The Big Dipper or Plough

Ursa Major, also called the Great Bear, is a famous constellation in the northern night sky. Its Latin name means the greater or larger bear. Long ago in ancient times, the astronomer Ptolemy included it in his list of 48 constellations. Today, astronomers recognize it as the third largest of the 88 modern constellations. It sits right near Ursa Minor, which is known as the lesser bear. People have looked up at these stars and told stories about them for thousands of years.

Most people recognize Ursa Major because of seven bright stars inside it. These stars form a pattern called an asterism. In the United States and Canada, this shape is known as the Big Dipper. In the United Kingdom, people call it the Plough. It looks just like a giant spoon or a farm tool. Two of its stars point directly toward Polaris, which is the northern pole star found in Ursa Minor. Because of this, travelers have used Ursa Major for centuries to find their way north.

This constellation is visible all year round from most places in the Northern Hemisphere. Because it stays above the horizon near the North Pole, it is called a circumpolar constellation. It has inspired people across many cultures and eras. It even appears proudly on the modern flag of Alaska.

How to Find Ursa Major in the Night Sky
Amazing Deep-Sky Objects in Ursa Major
Myths and Stories from Around the World
Ursa Major in Art and Flags
Fun Facts About Ursa Major
Images for kids
See also

How to Find Ursa Major in the Night Sky

Ursa Major and Polaris with names of bright stars in the Big Dipper

Ursa Major covers a very large section of the northern sky. In 1930, an astronomer named Eugène Delporte set its official borders for the International Astronomical Union. It forms a big shape with 28 sides in the equatorial coordinate system. Astronomers measure sky positions using right ascension and declination, which work like longitude and latitude on Earth. Ursa Major sits between eight other star patterns, including Draco, Boötes, Canes Venatici, Coma Berenices, Leo, Leo Minor, Lynx, and Camelopardalis.

The easiest way to spot Ursa Major is by searching for the Big Dipper. Its seven bright stars shine clearly against the dark background. Six of these stars are bright second magnitude objects. The handle of the dipper forms the long tail of the bear. The bowl of the dipper forms part of the bear's back and body.

Bright Stars of the Big Dipper

The constellation Ursa Major as it can be seen by the unaided eye

The Big Dipper contains seven primary stars that make its famous shape:

Dubhe is an orange giant star and the second-brightest star in the group. Its name comes from an Arabic word meaning bear.
Merak sits at the bottom corner of the bowl. Its name means the flank or loins of the bear.
Phecda forms the inner lower corner of the bowl. Its name means thigh.
Megrez is the dimmest of the seven stars. It connects the bowl to the handle, and its name means the base of the tail.
Alioth is the brightest star in Ursa Major. It is a special magnetic star called an Ap star, which belongs to a group of chemically peculiar stars.
Mizar sits in the bend of the handle. It forms a famous double star with a dimmer companion star called Alcor.
Alkaid marks the very tip of the handle. It is a hot blue star and the third-brightest star in the constellation.

Five of these stars share a similar proper motion across space. They travel together in a group called the Ursa Major Moving Group, moving toward the constellation Sagittarius. Only Dubhe and Alkaid are moving in different directions.

Finding the North Star

Ursa Major and Ursa Minor in relation to Polaris

You can use Ursa Major like a giant compass in the sky. The two stars on the outer edge of the bowl, Merak and Dubhe, are known as pointer stars. If you draw an imaginary line from Merak straight through Dubhe and keep going, you will find Polaris. Polaris is also known as the North Star.

Polaris sits directly above Earth's geographic North Pole. When you face Polaris, you are looking true north. Sailors and explorers relied on this simple trick for navigation across open oceans and vast deserts.

Other Star Patterns

Ursa Major contains other fun patterns beyond the dipper. In ancient Arab culture, people saw three pairs of stars along the southern edge as the footprints of a jumping gazelle. These pairs include Nu and Xi, Lambda and Mu, and Iota and Kappa. In China, these three steps were called Santai, while in ancient India they were called Trivikrama.

Amazing Deep-Sky Objects in Ursa Major

The Pinwheel Galaxy

Ursa Major looks out into deep space, away from the thick dust of our own Milky Way. This clear view allows us to see many distant galaxies and glowing clouds of gas called nebulae.

Bright Galaxies

Ursa Major holds several spectacular galaxies:

M81, also called Bode's Galaxy, is a gorgeous spiral galaxy about 11.8 million light-years away. It has a bright center of older stars and graceful arms filled with young stars.
M82, also called the Cigar Galaxy, sits right next to M81. The two are interacting gravitationally, which pulls on their gas clouds. M82 shines brightly in the infrared spectrum as a starburst galaxy where new stars form rapidly. In 2014, astronomers saw an exploding star called SN 2014J, which was a Type Ia supernova.
M101, known as the Pinwheel Galaxy, is a giant spiral galaxy seen face-on. It has bright regions of active star formation glowing with strong ultraviolet light.
NGC 2787 is an interesting lenticular galaxy with a central bar, similar to a barred spiral. It is surrounded by ancient balls of stars called globular clusters.
NGC 3079 is a spiral galaxy with an enormous bubble of gas at its center powered by a supermassive black hole creating strong superwinds.
NGC 3310 is another energetic starburst galaxy that collided with a smaller galaxy long ago.
NGC 4013 is a spiral galaxy turned sideways, showing a dark band of cosmic dust called a dust lane.
I Zwicky 18 is a small dwarf galaxy that contains very old stars dating back billions of years.

Astronomers also pointed the famous space telescope at an empty-looking patch near Delta Ursae Majoris. This created the historic Hubble Deep Field image, revealing thousands of ancient galaxies across the universe.

Nebulae and Variable Stars

Inside Ursa Major, you can find the Owl Nebula, also known as M97. It is a glowing planetary nebula that looks like the round face of an owl with two dark eyes. The astronomer Pierre Méchain discovered it in 1781.

Ursa Major also contains interesting stars:

W Ursae Majoris is a famous contact binary star system. In this system, two stars touch each other and share stellar material, changing their brightness regularly as a variable star.
47 Ursae Majoris is a star much like our Sun that hosts an extrasolar planetary system. Astronomers have found planets there, including 47 Ursae Majoris b, 47 Ursae Majoris c, and 47 Ursae Majoris d, which are gas giants with sizes compared to the mass of Jupiter.
Another interesting star is HD 80606, which has a planet named HD 80606 b. This giant planet travels along an extreme oval orbit, moving close to its star at periapsis and far away at apoapsis due to the Kozai mechanism.

Meteor Showers

Earth passes through streams of space dust left behind by comets in this constellation. The Kappa Ursae Majorids produce a steady meteor shower every November. Other showers include the Alpha Ursae Majorids and the October Ursae Majorids, which send shooting stars across autumn skies.

Myths and Stories from Around the World

Ursa Major shown on a carved stone in Scotland

People across the world have looked at Ursa Major and created wonderful legends about it. Scholars in Indo-European studies believe bear stories about these stars started over 13,000 years ago during the ancient Cosmic Hunt tradition.

Greek and Roman Myths

In Greek mythology, a kind maiden named Callisto roamed the wild forests as a companion to the goddess Artemis (known as Diana in Roman mythology). The king of the gods, Zeus (called Jupiter by the Romans), admired her greatly. However, his wife Hera (known as Juno) grew jealous and transformed Callisto into a wild bear.

Years later, Callisto's son Arcas went hunting in the forest and met the great bear. Not knowing it was his mother, Arcas raised his spear. To prevent harm, Zeus quickly grabbed them both and placed them into the starry sky. Callisto became Ursa Major, and Arcas became the constellation Boötes. The Roman poet Ovid told this story, describing how Callisto came from the beautiful land of Arcadia. The Greek writer Aratus noted that Ursa Major never sets below the ocean horizon in Greece, turning forever around the pole.

Stories from Asia

Ursa Major has deep meaning across Asia. In ancient Hinduism, the seven stars of the Big Dipper represent the Saptarshi, seven wise teachers described in the ancient Rigveda text. The front pointer stars show the way to the northern pole star, which honored a faithful young prince named Dhruva and the god Vishnu.

In China and Japan, the Big Dipper is called the North Dipper. Each star has an ancient name, such as Pivot, Jade, and Pearl. In Shinto belief, the stars honor Ame-no-Minakanushi, an ancient and revered spirit called a kami. In Korea, a folklore tale says seven loving brothers placed stepping stones across a river to help their mother, and their spirits became the seven bright stars.

In Southeast Asia, people saw other shapes. In the Burmese language, the stars form a giant crustacean like a crab or lobster. In the Javanese language and Malay language, the stars represent a great sailing vessel called a jong.

Native American Traditions

Many Native American nations saw a bear in this star pattern. The Haudenosaunee people told a story where the bowl of the dipper is a bear, and the three handle stars are hunters following it. The first hunter carries a bow, the second carries a cooking pot (represented by the little star Alcor), and the third carries wood for a fire.

The Lakota people call the pattern the Great Bear. The Wampanoag people also called it a bear, while the Wasco-Wishram people told stories of wolves placed in the sky by the clever Coyote.

European Legends

In northern Europe, the Old Norse religion saw the dipper as a wagon belonging to the god Woden. In the Finnish language, the dipper is called Otava, which originally meant a wooden weir used to catch salmon. Finnish stories say the first bear came down to Earth from Ursa Major in a sparkling golden basket.

The Sámi languages describe the constellation as the powerful hunting bow of an archer named Fávdna. This cosmic bow aims across the sky, pointing near Stella Polaris, which keeps the night sky in balance.

Ursa Major in Art and Flags

Ursa Major appears in famous literature, including poems by Homer, Shakespeare, and Tennyson. In modern history, the constellation appeared in the famous American song Follow the Drinkin' Gourd, where travelers used the Big Dipper to travel north toward freedom.

Famous artists have also celebrated these stars. The Dutch artist Vincent van Gogh painted the dipper sparkling above water in his masterpiece Starry Night Over the Rhône. Author H. A. Rey, who wrote beloved children's books, drew a clever diagram in his astronomy book showing Ursa Major shaped like a swimming polar bear.

Fun Facts About Ursa Major

It is the third-largest constellation in the entire sky.
If you look closely at the middle star in the handle of the Big Dipper, called Mizar, you might see a tiny star right next to it called Alcor. In ancient times, people used to test their eyesight by seeing if they could spot both stars.
The stars in the Big Dipper are at different distances from Earth. Some are about 60 light-years away, while others are over 100 light-years away. A light-year is the distance light travels in one year—about 6 trillion miles!
Because it is so far north, Ursa Major is "circumpolar" for most people in the Northern Hemisphere. This means it never sets below the horizon; it just circles around the North Star all night long.