System Bus
Many Union systems have more than one planet colonized and there are many systems where every large enough piece of Celestial real estate is utilized in some fashion.
Transmatter Tunnel systems are only available in the most advanced core systems connecting the most frequented destinations with in a system. Other destinations may have a System Tram , but many larger systems haveSpace Bus services that service destinations within a system only. Often running on a loop like course and service several destinations in timed schedules.
There is no standard bus model. They type of vehicle is often determined by local needs.
For example the local busses serving Klack systems have very large passenger capacities, while the busses serving within Boloth systems are capable of transporting five to ten Boloths at a time.