high-velocity star

High-velocity stars are celestial bodies with exceptionally large velocities relative to the Sun. These stars exhibit motions that deviate significantly from the typical patterns observed in the Milky Way Galaxy. For instance, Kapteyn's star, a nearby example, possesses a radial velocity of -245 km/sec, indicating a substantial speed and direction of movement through space.1

The measurement of a star's motion involves determining both its proper motion (movement across the line of sight) and its radial velocity (movement along the line of sight towards or away from an observer). While astronomers can precisely measure these for stars near the Sun, they often rely on radial velocity data for more distant objects to understand large-scale stellar movements within the galaxy. The high velocities of these stars can sometimes be a reflection of the Sun's own orbital motion around the galaxy.1