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At present, Polaris is the closest visible star to the north celestial pole, only 0.7 degrees away.  As such, the star is almost in a direct line with the Earth's [[axis]] of rotation.  From an observer on Earth, the star appears virtually motionless as the night goes on, with all the other celestial objects in the northern sky seemingly orbiting it.  At present, due to the [[precession of the equinoxes]], the celestial pole is actually moving closer to Polaris, and will reach its closest in the year 2105 before pulling away.<ref>http://stars.astro.illinois.edu/sow/polaris.html</ref>

At present, Polaris is the closest visible star to the north celestial pole, only 0.7 degrees away.  As such, the star is almost in a direct line with the Earth's [[axis]] of rotation.  From an observer on Earth, the star appears virtually motionless as the night goes on, with all the other celestial objects in the northern sky seemingly orbiting it.  At present, due to the [[precession of the equinoxes]], the celestial pole is actually moving closer to Polaris, and will reach its closest in the year 2105 before pulling away.<ref>http://stars.astro.illinois.edu/sow/polaris.html</ref>

Because of the 26,000 year axial precession of the Earth, Polaris was not always the pole star, nor will it be in the future.  Past pole stars include [[Beta Ursae Minoris]] from 1500 BC until 500 AD and Alpha Draconis ([[Thuban]]) in around 3000 BC, and [[Vega]] around 12,000 BC.  In the future, [[Deneb]] will become the north star around 8000 AD and Vega in around 14,000 AD.  Eventually in 27,800 AD Polaris will be the north star once again, but it will not be as close to the celestial pole this next time around, due to the star's proper motion.<ref>Norton, Arthur P. (1973). Norton's Star Atlas. Edinburgh: Sky Publishing. p. 10. ISBN 0-85248-900-5.</ref>

Past pole stars include [[Beta Ursae Minoris]] from 1500 BC until 500 AD and Alpha Draconis ([[Thuban]]) in around 3000 BC. and [[Vega]] around 12,000 BC.<ref>Norton, Arthur P. (1973). Norton's Star Atlas. Edinburgh: Sky Publishing. p. 10. ISBN 0-85248-900-5.</ref>

[[Category:Astronomy]]

[[Category:Astronomy]]