What star is labeled Alpha Ursa Minoris?

The star labeled Alpha Ursae Minoris is Polaris. It is better known as the North Star or Pole Star and is the brightest star in the constellation Ursa Minor, the Little Bear.

The designation Alpha Ursae Minoris follows the Bayer system, which commonly assigns Greek letters to stars within a constellation. “Alpha” generally identifies the leading or brightest star, while “Ursae Minoris” is the Latin possessive form meaning “of the Little Bear.” Polaris is actually a multiple-star system, with the visible primary component accompanied by smaller stellar companions.

Polaris appears close to the north celestial pole, so the northern night sky seems to rotate around it. This makes it useful for navigation, although it is not exactly at the pole and slowly changes position over thousands of years because Earth’s axis precesses. Polaris is also a Cepheid variable star, meaning its brightness changes in a regular cycle.