Three astronauts. Two cosmonauts. One handshake 140 miles above Earth. On July 15, 1975, NASA commander Thomas Stafford and Soviet commander Alexei Leonov clasped hands through the hatchway of their linked spacecraft, becoming the first humans to meet in orbit between rival superpowers. The Apollo-Soyuz Test Project launched that same day: a Soviet Soyuz capsule lifted off from Baikonur Cosmodrome first, followed seven and a half hours later by an American Apollo capsule from Kennedy Space Center. The two craft rendezvoused and docked on July 17, opening a passage that Cold War politics had spent decades sealing shut. Scientists conducted joint experiments over 44 hours of docked operations. The mission marked the final flight of an Apollo spacecraft and capped a decade of the Space Race with cooperation instead of competition. It proved that technical standards and human trust could bridge an ideological divide, a template that later made the International Space Station possible.