Assembly in Orbit

the joining of spacecraft or parts of spacecraft in orbit; it may be accomplished automatically or with the participation of the spacecraft crews. The aim of assembly in orbit may be the construction of large artificial earth satellites (space stations) or interplanetary vehicles from individual subassemblies that have been consecutively placed in near-earth orbit. Docking of spacecraft for assembly is preceded by the stages of search, location, approach, and tethering. Assembly in orbit may be performed outside the spacecraft by crew members or from inside the spacecraft with the use of manipulators. Assembly in orbit was first proposed by K. E. Tsiolkovskii.