Story of a Star Cluster

Meet M13, one of my favorite globular star clusters.

M13, also known as Messier 13 or the Hercules Cluster, is found—surprise surprise—in the constellation Hercules in the northern hemisphere.

The really cool thing about star clusters is that they look just as spectacular through a telescope as they do in a good image—that is, on a clear, dark night with good seeing conditions.

So…why am I showing you a picture of a star cluster? (Besides the fact that they’re gorgeous?)

Well…after all the talk I’ve done of stellar evolution, I know what you’re going to ask me next…how the heck do we know all this?

That’s a very good question—and one that star clusters can answer.

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