Today in History, July 15 / WikipediaThe Apollo–Soyuz Test Project crew. From left to right: Deke Slayton, Thomas Stafford, Vance Brand, Alexei Leonov and Valery Kubasov.

Thirty-eight years ago today, on July 15, 1975, the Soyuz 19 was launched in Kazakhstan, eight hours before a similar spacecraft, the Apollo 18, was launched in Florida. The two ships later docked in space, marking a symbolic joint-mission between the two superpowers and mirroring the ongoing process of detente that was taking place on Earth.