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Apollo-Soyuz Test Project

Apollo–Soyuz Test Project

Mission name	Apollo–Soyuz Test Project
Command module	CSM-111 14,768 kg (32,560 lb)
Spacecraft mass	16,780 kg/37,000 lb total (CSM plus 2,012 kg/4,440 lb Docking Module)
Crew size	3
Booster	Saturn IB
Launch pad	LC 39B Kennedy Space Center Florida, USA
Launch date	July 15, 1975 19:50 UTC
Landing	July 24, 1975 21:18 (1975-07-24T21:19) UTC
Mission duration	9 d 01 h 28 m
Number of orbits	148
Apogee	231 km (144 mi)
Perigee	217 km (135 mi)
Orbital period	88.91 m
Orbital inclination	51.75°
Distance travelled	~5,990,000 km (3,720,000 mi)
Left to right: Slayton, Stafford, Brand, Leonov, Kubasov
Related missions
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The Apollo–Soyuz Test Project (ASTP) flew in July 1975. It was the last Apollo mission, the first joint U.S./Soviet space flight, and the last manned US space mission until the first Space Shuttle flight in April 1981.

Though the mission included both joint and separate scientific experiments (including an engineered eclipse of the Sun by Apollo for Soyuz to take photographs of the solar corona) and provided useful engineering experience for future joint US/Russian space flights such as the Shuttle-Mir Program and the International Space Station, its primary purpose was symbolic. ASTP was a symbol of détente that the two superpowers were pursuing at the time, and it ended the tension of the Space Race.

This was astronaut Deke Slayton's only flight. He was chosen as one of the original Mercury Seven in April 1959 but had been grounded until 1972 for medical reasons.