The term 'Former Russian Orbiter' refers to the MIR spacecraft, which was a Soviet-era space station that operated in low Earth orbit from 1986 to 2001. It was the first modular space station and was assembled in orbit from 1986 to 1996. The MIR was the longest-operating space station in history and hosted a variety of international crews and experiments. It was eventually deorbited and burned up in the atmosphere in 2001.