Clusters in nature

[Tglad]

This is a great example of a cluster fractal... the solar system-

A few large objects like the sun and jupiter, about 200 moon size objects, loads of large rocks in the asteroid belts and rings of saturn, billions of small stones down as fine as dust.
Its the fractal that covers the largest scale range that I know.
So in fractal terms, it isn't a system containing different objects (planets, moons, asteroids, dust), its just a single cluster with a certain dimension (about 2 I think).

Another cluster is a volcanic cloud, here under a microscope-

Usually thought of as made of the separate items of fine dust, grit, hot pebbles and large rocks lifted into the sky.
In fractal terms we could say it is a single volcanic cluster.

Post here if you have any other good examples of clusters in nature