Star Profile Polaris

The more we find out about our guiding star, the more it fascinates us

Polaris, the North Star, is a single point in the night sky which the entire consortium of stars appears to revolve around. Despite being one of the most well-known stars in the sky, Polaris continues to confuse scientists. We still don’t know for sure how old the star is, or even exactly how far away it is from Earth.

The yellow supergiant is a Cepheid variable star, which means its brightness fluctuates by less than a tenth of a magnitude every few days. A common misconception is that Polaris is the brightest star in the sky, but this position is actually held by Sirius, with Polaris only ranking 48th in terms of luminosity.

Since Polaris isn’t incredibly bright or visible to us, how has it been our famous guiding star, escorting travellers for centuries? The answer is its location. Polaris is our one constant in the perpetually moving night sky, remaining in almost the exact same position above the northern horizon all year round. In Mongolian mythology, it’s considered to be the peg that holds the world together, and in Norse mythology, it was the end of a spike around which the sky rotates.

No matter where you find yourself in the Northern Hemisphere, if you locate Polaris, you know you’re facing north. If you want to take navigation one step further, you can measure the distance between Polaris and the horizon to discover a second valuable data point: your latitude. If you were to stand at the North Pole, Polaris would appear almost directly overhead – the star is slightly offset from the true north celestial pole by less than a degree.