How are space stations classified? Explain in short giving examples.
Space stations are broadly classified into two types depending on whether they are launched as a single unit or not:
1. Monolithic space stations – Monolithic space stations are intended to be constructed and launched in one piece and then manned by a crew later. As such, monolithic stations generally contain all their supplies and experimental equipment when launched, and are considered “expended”, and then abandoned, when these are used up. E.g. Salyut, Skylab
2. Modular space stations – In modular space stations, a core unit is launched, and additional modules, generally with a specific role, are later added to that. This method allows for greater flexibility in operation, also removing the need for a single immensely powerful launch vehicle. E.g. Mir and International Space Station (ISS)