In our region of the Milky Way Galaxy, the stars are a long way apart. The Sun’s nearest neighbor is more than four light-years away — 25 trillion miles. In the core of a globular cluster, though, the stars are packed hundreds of times more densely. That means the stars are only a few light-months apart, or even light-weeks — much closer than in our own neighborhood.
One of the most prominent globular clusters is in Hercules, the strongman. M13 — the Hercules Cluster — is perhaps 25,000 light-years away. It contains several hundred thousand stars.
M13 and the other globular clusters are thought to be the oldest inhabitants of the Milky Way. So most of the stars in the cluster are more than 10 billion years old — more than twice the age of the Sun.
Such stars are fainter, redder, and less massive than the Sun. From a planet near the cluster’s middle, you’d see a whole bunch of stars in the night sky, and almost all of them would be yellow, orange, or red — remnants of the early galaxy.
M13 is low in the northeast at nightfall. It’s along the line that connects the top two stars in the “Keystone” — a lopsided square of stars that outlines the strongman’s torso. Under clear, dark skies, the cluster looks like a dim fuzzball. It’s easier to see if you look out of the corner of your eye. It’s an easy target for binoculars — the glow of an ancient family of stars.
Script by Damond Benningfield