bound cluster xuše-ye bandidé Fr.: amas lié A cluster of astronomical objects, such as stars or galaxies, held together by their mutual gravitational attraction. → bound system. |
unbound cluster xuše-ye nâbandidé Fr.: amas non lié A cluster of objects, such as stars or galaxies, in which the members are not tied together gravitationally. In such a cluster the members scatter through space following different directions. → bound cluster. |