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Polaris is not exactly at the celestial pole, as this time-exposure photo shows. In 2006 it was 42' away from the pole.

The North Star is a title of the star best suited for navigation northwards. A candidate must be visible from Earth and circumpolar to the north celestial pole. The current one is Polaris. It is the star at the end of the "handle" of the Little Dipper asterism in the constellation Ursa Minor. It is close to the celestial North Pole, but off by about two-thirds of 1°.

The North Star has been historically used by explorers to determine their latitude. At any point north of the equator the angle from the horizon to the North Star (its altitude) is the same as the latitude from which that angle was taken. For example, the angle to the North Star for a person at 30° latitude will be about 30°.

Polaris has a visual magnitude of 1.97 (second magnitude), which places it as the Fourth-Brightest star in the sky, though some people mistakenly think this is the brightest star in the night sky (which truly belongs to Sirius).

In 3000 BC the faint star Thuban in the constellation Draco was the North Star. At magnitude 3.67 (fourth magnitude) it is only one-fifth as bright as Polaris, the current North Pole Star (situated at 430 light-years away)

Gamma Cephei (also known as Alrai, situated at 45 light-years away) will become closer to the northern celestial pole than Polaris around 3000 AD, and be at its closest approach around 4000 AD. The "title" then will pass to Iota Cephei (ι Cephei, situated 115 light-years away) some time around 5200 AD. The first magnitude star Vega (26 light-years away) will then become the North Star by AD 14,000, due to Precession of the equinoxes.

Currently, there is no South Star as useful as Polaris; the faint star σ Octantis is closest to the south celestial pole. However, the constellation Crux, the Southern Cross, points towards the south pole.

• Pole star

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