Spacecraft Bus

A satellite bus or spacecraft bus is the general model on which multiple-production satellite spacecraft are often based. The bus is the infrastructure of a spacecraft, usually providing locations for the payload (typically space experiments or instruments).

They are commonly used for geosynchronous satellites, particularly communications satellites, but are also used in spacecraft which occupy lower orbits, occasionally including low Earth orbit missions.

A bus-derived satellite would be used as opposed to a one-off, or specially produced satellite, such as Prospero X-3. Bus-derived satellites are usually customized to customer requirements, for example with specialized sensors or transponders, in order to achieve a specific mission.

(only commercially available models)

Some satellite bus examples include:

A bus typically consists of the following subsystems:

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