The brightest star in the constellation Ursa Major, approximately 123 light years from Earth. It is one of the seven stars that form the Big Dipper and aligns with Merak to point to Polaris.
[Medieval Latin, from Arabic ẓahr al-dubb al-'akbar, the back of the Great Bear, from dubb, bear; see dbb in the Appendix of Semitic roots.]
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