Thuban

noun Thu·ban \ thü-ˈbän \

Definition of Thuban

astronomy
: a white giant star of the fourth magnitude that is visible in the constellation Draco
  • Engineers had determined that these standing stones predict solar and lunar events as well as the position of Thuban, the polestar in ancient Phoenician times.
  • —Karen WrightDiscoverFebruary 1998
called also Alpha Draconis
Note: From about 4000 BC through 1800 BC, Thuban was the star closest to the north celestial pole. It was used (instead of Polaris) as the polestar during that time. The movement of the earth has caused it to drift away, but in another 20,000 years, it will once again qualify as the “North Star.”

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First Known Use of thuban

1855


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