Ursa Minor

Ursa Minor
Constellation
Ursa Minor
AbbreviationUMi[1]
GenitiveUrsae Minoris[1]
Pronunciation
Symbolismthe Little Bear[1]
Right ascension00h 00m to 24h 00m [1]
Declination65.40° to 90°[1]
QuadrantNQ3
Area256 sq. deg. (56th)
Main stars7
Bayer/Flamsteed
stars
23
Stars with planets4
Stars brighter than 3.00m3
Stars within 10.00 pc (32.62 ly)0
Brightest starPolaris[2] (1.97m)
Messier objects0
Meteor showersUrsids
Bordering
constellations
Visible at latitudes between +90° and −10°.
Best visible at 21:00 (9 p.m.) during the month of June[2].

Ursa Minor (Latin for 'Lesser Bear', contrasting with Ursa Major), also known as the Little Bear, is a constellation located in the far northern sky. As with the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the North American name, Little Dipper: seven stars with four in its bowl like its partner the Big Dipper. Ursa Minor was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor has traditionally been important for navigation, particularly by mariners, because of Polaris being the north pole star.

Polaris, the brightest star in the constellation, is a yellow-white supergiant and the brightest Cepheid variable star in the night sky, ranging in apparent magnitude from 1.97 to 2.00. Beta Ursae Minoris, also known as Kochab, is an aging star that has swollen and cooled to become an orange giant with an apparent magnitude of 2.08, only slightly fainter than Polaris. Kochab and 3rd-magnitude Gamma Ursae Minoris have been called the "guardians of the pole star" or "Guardians of The Pole".[3] Planets have been detected orbiting four of the stars, including Kochab. The constellation also contains an isolated neutron star—Calvera—and H1504+65, the hottest white dwarf yet discovered, with a surface temperature of 200,000 K.

  1. ^ a b c d e Cite error: The named reference boundary was invoked but never defined (see the help page).
  2. ^ a b Department of Astronomy (1995). "Ursa Minor". University of Wisconsin–Madison. Retrieved 27 June 2015.
  3. ^ "Star Tales – Ursa Minor". Retrieved 2024-07-22.