Ursa Major

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Ursa Major
Ursa Major
Click for larger image
List of stars in Ursa Major
Abbreviation: UMa
Genitive: Ursae Majoris
Right ascension: 10.67 h
Declination: +55.38°
Area: 1280 sq. deg. (3rd)
Main stars: 7, 20
Bayer/Flamsteed stars: 93
Stars known to have planets: 20
Bright stars: 7
Nearby stars: 8
Brightest star: ε UMa (Alioth) (1.76m)
Nearest star: Lalande 21185 ( ly)
Messier objects: 7
Meteor showers: Alpha Ursa Majorids
Bordering constellations: Draco
Leo Minor
Coma Berenices
Canes Venatici
Visible at latitudes between +90° and −30°
Best visible at 21:00 (9 p.m.) during the month of April
Big dipper.triddle.jpg
The Big Dipper or Plough.

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. All of the stars in the constellation 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.

Deep-sky objects[change | change source]

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[change | change source]

The Big Dipper (or Plough) within Ursa Major

The seven stars in the upper-left 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.

Other websites[change | change source]