Polaris, also known as the pole star is very close to the ‘North Celestial Pole’ (NCP). This is the central point at which the stars visually rotate around in the sky. If you were stood on the North Pole, Polaris would stay directly overhead and hardly move. No-matter where your location is, the pole star hardly moves all night and the rest of the stars rotate around it. This star has a number of uses…
- Finding North – if you draw an imaginary line from the pole star down to the horizon, this is North.
- Polar aligning telescopes – Astronomers in the Northern hemisphere use the pole star as an excellent guide for polar aligning a telescope to the NCP.
- Calculating your latitude – The altitude of the pole star at your location is always equal to your latitude.
Polaris is on the tail of Ursa Minor (The little bear). The Plough (or “big dipper”) is a good pointer to the pole star as shown below…