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Although stars appear "fixed" in the sky they do move very slowly with time and this so called "proper motion" is the apparent movement. Red dwarf star "Barnard's star" in Ophiuchus has the largest proper motion of all known stars. It takes 180 years to move 0.5 degrees, equivalent to the apparent diameter of the Moon.

Apparent movement of Barnard's star over a period of 20 years (credit:- Steve Quirk)

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