These expanding systems endowed with a positive energy he named "stellar associations" and proved their relatively young age.

The concept of stellar association was not immediately accepted by the astronomical community though.

Moving group or stellar association is a loose grouping of stars that are traveling together through space.

The fist conference was held in November 1951 on the topic of stellar associations.

This is a stellar association of stars that share a common origin.

Zeta Pegasi is not known to be a member of a stellar association.

This is a gravitationally unbound stellar association with an estimated age of 16-20 million years.

Previously only young bright stars were known in this stellar association.

The stars in stellar associations are moving away from one another so rapidly that gravitational forces cannot keep them together.

The group is then known as a stellar association, or a moving group.