10 Facts About Globular cluster

The low resolution of early telescopes prevented individual stars in a Globular cluster from being visually separated until Charles Messier observed M?4 in 1764.

Globular cluster coined the term globular cluster in his Catalogue of a Second Thousand New Nebulae and Clusters of Stars.

Globular cluster correctly concluded that the Milky Way's center is in the Sagittarius constellation and not near the Earth.

Globular cluster formation is prevalent in starburst regions and in interacting galaxies.

The stars found in a globular cluster are similar to those in the bulge of a spiral galaxy but confined to a spheroid in which half the light is emitted within a radius of only a few to a few tens of parsecs.

Therefore, the age of a single-population Globular cluster can be measured by looking for those stars just beginning to enter the giant star stage, which form a "knee" in the H–R diagram called the main-sequence turnoff, bending to the upper right from the main-sequence line.

When this gravothermal instability occurs, the central region of the Globular cluster becomes densely crowded with stars, and the surface brightness of the Globular cluster forms a power-law cusp.

In contrast, the effect of tidal shocks as a globular cluster repeatedly passes through the plane of a spiral galaxy tends to significantly accelerate core collapse.

The ultimate fate of a globular cluster must be either to accrete stars at its core, causing its steady contraction, or gradual shedding of stars from its outer layers.

The likelihood of close encounters between stars in a globular cluster can disrupt planetary systems; some planets break free to become rogue planets, orbiting the galaxy.