Star Cluster

Splashery stretches a drumhead over this Splash's outline, twelve inches across, and finds the ways it can ring. Its lowest is 570.0 Hz, 52 cents flat of D5, the nearest tine on the comb. The next fifteen are its overtones, and each one draws its own figure: sand gathers on the lines that stay still.

Tap it to make the cluster breathe in and out.

A globular cluster is a ball of hundreds of thousands of stars held together by their own gravity, packed tightest at the middle. Its stars are very old, among the oldest in our galaxy, and the Milky Way has about 150 of these clusters circling it.

Tap it and the cluster breathes: it draws in, swells out and settles, the core first and the outer stars a moment later, while a wave of sparkle runs out from the middle. Near the middle of a real cluster, the stars are packed far more tightly than the stars around the Sun.

Made in Splashery. Its code is MIT.

This link opens it in the Playground. To put it on your own page, add the element and one script tag. Every option.