(apparent motion in relation to the position of the Sun)
Proper motion of a star is its change in angular position
over time, corrected for the Earth's orbit,
measured in angle (e.g., arcseconds) per year.
If you could measure the position of an object at two instances
precisely one year apart, the angle in arcseconds between the
two measured positions would be its proper motion.
Proper motion is an indication of relative motion between the star
and the Sun, but does not fully characterize it, which
also requires knowing the distance to the star and the star's
Common proper motion is such motion when it is shared by
two stars, evidence they are a binary star.
Astrographic Catalog (AC)
Bruce Proper Motion Survey (BPM)
Frank Ross's Catalog (Ross)
Herschel Double Star Catalog (H)
Luyten Half-second Catalog (LHS)
Lowell Proper Motion Survey (G)
Luyten Palomar Survey (LP)
Luyten Two-Tenths Arcsecond Catalog (LTT)
Max Wolf's catalog of stars with proper motion
PPM Star Catalogue
SuperCOSMOS Sky Survey (SSS)