The cluster is about 28,000 light-years away in Capricornus. Like other globulars, it contains an old population held in a dense spherical system, but M30 is especially interesting because its core has undergone gravitational collapse, driving stars into an extremely concentrated center.
Hubble observations found two distinct populations of blue stragglers—stars that appear younger and bluer than the cluster’s ordinary old population. Their distribution preserves evidence of different formation routes and of the cluster’s internal dynamical evolution.
So the small glow in the telescope is not static. Over immense spans of time, encounters between stars and binary systems redistribute energy, move stars inward or outward, and alter what kinds of stars appear in different parts of the cluster.
M30 looks quiet because stellar dynamics move slowly on a human clock. On the cluster’s clock, it has been sorting itself for billions of years.
Sources: NASA Hubble Messier Catalog, “Messier 30,” and Hubble studies of blue stragglers in M30.
