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Ursa Major Moving Cluster

A loose group of stars, widely scattered about the sky, with similar space velocities (about 14 km/s in the direction of eastern Sagittarius), that includes five of the seven major members of the Big DipperMerak (Beta), Phad (Gamma), Megrez (Delta), Alioth (Epsilon), and Mizar (Zeta) – as well as Alphekka (Alpha Coronae Borealis) and Sirius (Alpha Canis Majoris). With its center located about 75 light-years from us, about half the distance of the Hyades, it is the nearest star cluster to the Sun. Its proximity and its size (some 30 light-years long by 18 light-years wide) mean that it covers an enormous portion of the sky.

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