proper-motion membership自行成员星
proper-motion ratio自引率
common proper-motion pair共自行星对于;共自行星对
common proper-motion binary共自行双星
common n proper-motion binary共自行双星
common n proper-motion pair共自行星对
proper motion star[天] 大自行恒星
restricted proper motion[天] 限制性自行
stellar proper motion恒星自行
N(名词) the very small continuous change in the direction of motion of a star relative to the sun. It is determined from its radial and tangential motion 自行