WIKIARCHIVES.SPACE

At the Gagarin Cosmonaut Training Center in Star City, Russia, former Russian cosmonaut Alexey Leonov (left) and former NASA astronaut Thomas Stafford (right) dig a site for the planting of a ceremonial tree July 16 during a celebration of the 40th anniversary of the Apollo-Soyuz mission that opened a new era of space cooperation between the U.S. and Russia. Stafford commanded the Apollo spacecraft and Leonov commanded the Soyuz 19 spacecraft that docked on July 17, 1975 in the first-ever linkup of American and Russian space vehicles.