Soyuz 5 (,
Union 5) was a
Soyuz mission using the
Soyuz 7K-OK spacecraft launched by the
Soviet Union on 15 January 1969, which docked with Soyuz 4 in orbit. It was the first-ever docking of two manned spacecraft of any nation, and the first-ever transfer of crew from one space vehicle to another of any nation, the only time a transfer was accomplished with a
space walk – two months before the US
Apollo 9 mission performed the first ever internal crew transfer.