World’s first joint space project uniting different countries started 39 years ago.

The ground for Soyuz-Apollo experimental project was laid on 26-27 October, 1970, when Soviet and American specialists dealing with the issues of manned spacecrafts approaching and docking facilities met in Moscow for the first time.

On May 24, 1972, USSR and USA signed peaceful space exploration and use collaboration agreement .

The Agreement stipulated the docking of Soviet Soyuz spacecraft with the American one Apollo in the open space, after that the cosmonauts had to visit the newly docked spacecraft.

In December 2-8, 1974, in accordance with the Soviet program of joint space experiment preparation Soyuz-16 modernized spacecraft performed the flight.

In the course of the flight life support system was tested (particularly, the depressurization of the modules to 520 millimeters of mercury) as well as automatic system and several nodes of docking facilities, several methods of joint scientific experiments conducting were practiced,  assembly orbit of 225 km altitude was formed.

On July 15, 1974, at 15.20  Soyuz-19 spacecraft with the cosmonauts Alexei Leonov (commander) and Valery Kubasov (flight engineer) onboard was launched from Baikonur spaceport. Later at 22.50 Apollo was launched from cape Canaveral. Apollo crew comprised American astronauts Thomas Stafford (crew commander), Donald Slayton (pilot) and Vance Brand (docking module pilot).

The first docking of international spacecraft took place on July 17, 1975 and was a success.