Apollo-Soyuz Test Project

The Apollo-Soyuz Test Project was the first crewed U.S.-Soviet space mission and the first international docking between crewed spacecraft. Soyuz 19 launched from Baikonur on July 15, 1975, followed several hours later by an Apollo spacecraft launched from Kennedy Space Center on a Saturn IB. The two spacecraft docked on July 17 and remained linked for nearly two days while Thomas Stafford, Vance Brand, Deke Slayton, Aleksei Leonov, and Valeriy Kubasov exchanged visits, conducted joint experiments, and tested docking procedures that would influence later international missions. Soyuz returned on July 21, while Apollo continued independent operations before splashing down on July 24. The mission is widely treated as the symbolic end of the early Space Race and a practical starting point for later U.S.-Russian crewed cooperation.