What would a list of astronomical objects in order of increasing size look like?

Hi Richard,

The list of things by size might go:

Planet, solar system, galaxy, cluster of galaxies, cosmological
structures, whole universe.

Galaxies making up a cluster are usually bound to one another by their
mutual gravity. This prevents the cluster from separating in the
general expansion of the universe.

Cosmological structures are clusters of galaxy clusters. They make up
great sheets of matter surrounding nearly empty voids, in a pattern
rather like a network of soap bubbles surrounding pockets of air.

Best wishes,
-Neal.

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