Polaris or Alpha Ursae Minoris is probably one of the best known stars in the Northern hemisphere due to the fact that it is at present, the North Star or Pole Star. Polaris shines at magnitude 2.0 and is a supergiant with a luminosity of around 9,000 suns. The star is also a lovely double star with a white companion shining at magnitude +1.2 easily seen with a 3 inch telescope. The whole system is about 820 light years distant.
Of course, the stars real claim to fame is the fact that it is the Pole Star. However, this has not always been the case because of a phenomenon called precession which is the slow change in the orientation of the Earth's axis (due to the gravity of the Sun & Moon), which makes the north celestial pole trace a 47° diameter circle on the celestial sphere every 25,800 years!
Recollect how a spinning top spins and the arc it creates at the top and you're there. Because of this, during different epochs, different stars have been and will be the Pole Star. So, when the pyramids were built by the Egyptians (or constructed by aliens) some 4,600 years ago, Thuban (Alpha Draconis) was the Pole Star and 12,000 years ago Vega (Alpha Lyrae) was the Pole Star.
Polaris is located in the constellation of Ursa Minor (Little Bear) and for Northern observers is always visible which given it's position should be quite obvious. A tiny cluster of stars just south of Polaris is known as the engagement ring with Polaris being the diamond. How nice, and can be seen in good binoculars. Go look and marvel at the size of that diamond compared to our beautiful Sun, without which we would not exist.
Keep questioning reality and keep looking up!
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