The north pole star, Alpha Ursae Minoris, magnitude 2.0. It is an F-type supergiant, 433 l.y. away. Polaris is currently less than 1° from the north celestial pole, and the distance is gradually decreasing due to precession; it will be closest to the pole, just under ½°, around the year 2100. Polaris is a Cepheid variable with a period of 4 days and a small range, originally about 0.1 mag. but which decreased during the twentieth century to only a few hundredths of a magnitude now. Polaris is also a spectroscopic binary with a period of 30 years. From observations with the Hubble Space Telescope this companion appears to be a dwarf F star. There is a more distant companion of magnitude 8.2 which can be seen with a small telescope.

http://hubblesite.org/image/1842/news_release/2006-02