Crash Course Astronomy: Star Clusters

Last week's episode of Crash Course dealt with stars in multiple systems: Binaries, triples, quadruples, and more. Most stars in the sky are multiples! It turns out that stars can be in even bigger, more complex systems. Most stars may be born by the thousands in clusters. Maybe even the Sun was. Clusters are gorgeous astronomical objects, but they're more than that: They're astrophysical laboratories, allowing us to puzzle out a lot of very cool information about the starry denizens that live t...