star of greatest proper motion | |
A star's proper motion is its real motion through space across our line of sight as projected onto the sky. It depends on the star's real velocity in the direction at right angles to the line joining it and the Sun, and also on its distance: even if a star is moving rapidly, its travel will not be apparent if it is at a very great distance. Barnard's star is one of the closest to the Sun - the next nearest after Proxima Centauri and the binary pair Alpha Centauri A and B. Barnard's star is also moving towards the Sun at 0.036 light years per century. In about 9000 years, it will be the nearest star in place of Proxima Centauri. |