There are many known asteroid bases within Union space and beyond. Asteroids, if available for the purpose of the base is needed, are prefered over artificial stations.
Types of common asteroid bases:
(**) Trading posts and supply posts outside the juristiction or control of major space faring societies tend to attract the lawless, the freelancers , smugglers and pirates . Often becoming famous or rather infamous pirate nests or ports. Among the most famous was Brhama Port in the Shattered System (Free Space )