moving group

A moving group is an observed group of stars that are moving in pretty much the same direction. It may be identified by checking the proper motion of stars in a portion of the sky, and checking the distance by some means. There may be other stars visible in the same region of the sky that do not share the same motion. Such moving groups are considered evidence that the stars share a common origin, formed at roughly the same time within the same star-forming region, i.e., that the group is the remnant of an open cluster or stellar association that has spread out.