स्वतःभोवती फिरणाऱ्या एखाद्या वस्तूचा अक्ष त्या वस्तूला तिच्या बाह्य पृष्ठभागावर ज्या ठिकाणी छेदतो त्या बिंदूंना त्या वस्तूचे ध्रुव असे म्हणतात.

Polaris is a star in the northern circumpolar constellation of Ursa Minor. It is designated α Ursae Minoris and is commonly called the North Star or Pole Star. With an apparent magnitude that fluctuates around 1.98, it is the brightest star in the constellation and is readily visible to the naked eye at night. The position of the star lies less than 1° away from the north celestial pole, making it the current northern pole star. The stable position of the star in the Northern Sky makes it useful for navigation.