Ursa Major Constellation Facts

The 'Big Dipper', which is part of the Ursa Major constellation, is highlighted in yellow.

Ursa Major is visible all year in the Northern hemisphere.
The constellation is partially visible in some northerly regions of the Southern hemisphere.
Ursa Major is Latin for Great Bear, although the constellation is based on Greek mythology.
Ursa Major is associated with the nearby constellation of Ursa Minor (Little Bear).
The very recognizable Big Dipper, also known as The Plough, is part of the Ursa Major constellation.
The Big Dipper is an asterism, which are stars which form simple patterns in the night sky, usually asterisms bare the same name as the constellation they appear in, but this is obviously not the case with the Big Dipper.
The two stars which form the outer bowl of the Big Dipper point towards the North Star, Polaris.
Polaris is the brightest star in the constellation of Ursa Minor.
The tail of Great Bear includes the brightest star in the Ursa Major constellation, Alioth.
Native North Americans also perceived the pattern of stars as a bear.

Ursa Major Mythology

An artistic representation of Ursa Major, the Great Bear.

The myth of Ursa Major involves the character Callisto from Greek mythology, a beautiful woman who was an attendant of Artemis, the Goddess of hunting and protector of girls. Callisto took a vow of chastity and became a favored hunting companion of Artemis. One day Zeus noticed the beautiful young Callisto and tricked her into breaking her vow of chastity. As a result she fell pregnant and was banished into the wild by Artemis, eventually Callisto gave birth to a son, Arcas.

Hera, the wife of Zeus soon heard of her husband’s indiscretion and took vengeance on Callisto by turning her into a bear. One day, after many years of wandering the wilderness alone, Callisto accidently encountered her long lost son. Not recognizing his mother Arcas is about to kill Callisto when Zeus intervenes and sends her into the heavens as Ursa Major (Great Bear) and her son as Ursa Minor (Little Bear).

Main Stars in the Ursa Major Constellation

The number next to each star is its apparent magnitude, its brightness from our point of view on Earth, the lower the number the brighter the star in the night sky.

Alkaid
Also known as Eta Ursae Majoris, Alkaid is a bluish-white main sequence star with surface temperatures around 3 times that of the sun, it's also around 3 and half times larger in radius than the sun.

Mizar-Alcor
A six star system around 80 light years from Earth, Mizar consists of two pairs of binary stars while Alcor consist of one pair, the two are separated by a distance of one light year.

Alioth
Also known as Eta Ursae Majoris, at a distance of around 80 light years from Earth Alioth is the brightest star in the constellation, it has surface temperatures twice that of the sun with a radius around 4 times larger.

Megrez
A white main sequence star one and a half times larger in mass and radius than the sun, also known as Delta Ursae Majoris the star is around 60 light years from Earth.

Dubhe
Also known as Alpha Ursae Majoris, Dubhe is an orange giant star around 120 light years from Earth, Dubhe is the second brightest star in the constellation.

Muscida
At a distance of around 180 light years from Earth Muscida is a yellow giant star with a radius 14 times larger than the sun, the star is also known as Omicron Ursae Majoris.

Talitha
Also known as Iota Ursae Majoris, Talitha is a four star system consisting of two pairs of binary stars around 45 light years from Earth.

Merak
A white main sequence star with around three times the mass and radius of the sun, also known as Beta Ursae Majoris the star has surface temperatures around twice as hot as the sun, drawing an imaginary line through Merak and Dubhe will point you to the North star.

Phecda
Another white main sequence star similar in radius and mass to Merak, also known as Gamma Ursae Majoris the star is around 80 light years from Earth.

Tania Borealis
At around 140 light years from Earth this white star has around 2 and half times the mass and radius of the sun.

Tania Australis
A red giant star around 240 light years from Earth, Tania Australis is around 75 times larger in radius than the sun.

Alula Borealis
An orange giant star around 400 light years from Earth, Alula Borealis is around 60 times larger in radius than the sun.

Alula Australis
A four star system consisting of two pairs of binary stars around 30 light years from Earth, the primary stars in both pairs are sun like stars, while their companions are thought to be red dwarfs.

Finding Ursa Major - Northern Hemisphere

The chart shows the position of Ursa Major over most of the United States in mid-winter at 8 pm. This chart can also be applied to other areas of the Northern hemisphere such as Canada, the UK and Europe. In the Northern hemisphere Ursa Major never sets below the horizon, as a result it is visible all year in the night sky.

From January to March the constellation will first appear in the north-eastern night sky at around 6 pm, between midnight and 1 am it will be almost directly overhead before disappearing in a north-westerly direction as day breaks around 7 am.

From April to June Ursa Major will first appear overhead at around 9 pm, as the night moves on it will move lower towards the horizon in a north-westerly direction until day breaks around 6 am.

From July to September the constellation will be become visible around 10 pm in the north-west, it will gradually become lower on the horizon in a more northerly direction before day breaks around 6 am.

From October to December it will appear low on the horizon in the north-west at around 6 pm, it will stay quite low on the horizon moving eastwards until around midnight before moving higher in the sky until day breaks around 6 am.

Finding Ursa Major - Southern Hemisphere

The chart shows the position of Ursa Major over Northern Australia in mid-spring at 8 pm. This chart can also be applied to more northerly areas of the Southern hemisphere. In Southern Australia and other southerly regions of the hemisphere Ursa Major is not visible.

From January to March the constellation will become partially visible at around 11 pm from the north-east, as the night moves on the entire constellation will become visible but will remain quite low on the horizon before disappearing as day breaks around 6 am.

The Autumn months of April to June are the best time of year to observe Ursa Major, it will appear in a north-easterly direction at around 7pm, moving westwards before dipping below the horizon around 2 am.

July to September the constellation will make a very brief appearance in the north-west between 7 and 8 pm and will only be partially visible.

From October to December Ursa Major will once again make a very brief and early appearance between the hours of 5 and 6 am, this time in the north-east and once again it will only be partially visible.