Ursa Major

Ursa Major is a constellation that can be seen in the northern hemisphere and part of the southern hemisphere. Its name means Great Bear in Latin. It was named that because many different groups of people around the world have thought that its stars look a lot like a bear with a long tail. It is often used as a symbol for north.

Ursa Major

Constellation
List of stars in Ursa Major
Abbreviation	UMa
Genitive	Ursae Majoris
Pronunciation	/ˈɜːrsə ˈmeɪdʒər/, genitive /ˌɜːrsiː məˈdʒɒrɪs/
Symbolism	the Great Bear
Right ascension	10.67
Declination	+55.38
Quadrant	NQ2
Area	1280 sq. deg. (3rd)
Main stars	7, 20
Bayer/Flamsteed stars	93
Stars with planets	20
Stars brighter than 3.00m	7
Stars within 10.00 pc (32.62 ly)	8
Brightest star	ε UMa (Alioth) (1.76m)
Messier objects	7
Meteor showers	Alpha Ursa Majorids Leonids-Ursids
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.

"Big Dipper" redirects here. For other uses, see Big Dipper (disambiguation).

According to Greek mythology, Ursa Major was once the beautiful maiden Callisto, whom the god Zeus had an affair with. In order to protect her and their son, Arcas, from his jealous wife Hera, Zeus turned Callisto and Arcas into bears. He then picked up the bears by their short, stubby tails and threw them into the sky.^[1]

The constellation cannot be seen from the southern areas of Patagonia, South Africa, Australia, and all of New Zealand except the Northland region.

Deep-sky objects

Several bright galaxies are found in Ursa Major, including the pair Messier 81 (one of the brightest galaxies in the sky) and Messier 82 above the bear's head, and the Pinwheel galaxy (M101), a beautiful spiral galaxy northwest of the star η Ursae Majoris. Other well-known spiral galaxies are NGC 4102, NGC 4605, Messier 108 and Messier 109. The constellation has about 50 galaxies that can be seen with a small telescope. The Owl nebula, the brightest planetary nebula, can be found along the bottom of the bowl of the Big Dipper.

The Big Dipper

The Big Dipper (or Plough) within Ursa Major

The seven stars in the northeast corner of Ursa Major form an asterism called the Big Dipper (or the Plough in Great Britain). This group has been recognized by almost all groups of people who live or lived in places where it can be seen in the sky and it is one of the best-known star patterns. The Big Dipper is helpful in finding the north star because an imaginary line drawn through the two stars on the right side will point directly at the north star. These two stars are called The Pointers and they are very important on navigation by stars.

All of the stars in the Big Dipper except Dubhe and Alkaid are moving toward the same point in the sky through proper motion. This group of stars is known as the Ursa Major Moving Group.

References

1. "Ursa Major in Greek Mythology| the myth of Zeus and Callisto". 20 March 2011.

Other websites

• The Deep Photographic Guide to the Constellations: Ursa Major