Tags: Space Station.
Kosmos 1686 (Russian: Космос 1686 meaning Cosmos 1686) also known as TKS-4 was a heavily modified TKS spacecraft which docked unmanned to the Soviet space station Salyut 7 as part of tests to attach scientific expansion modules to stations in Earth orbit. The module which docked to the station was the FGB component of a TKS vehicle launched on 1985-09-27 and was designed to test systems planned for use on the Mir Core Module.
