July 17th, 1975 was a historic date for space missions. On this date, the U.S. spacecraft Apollo 18 and the Soviet Soyuz 19 met and docked in space. It was part of a mission trying to develop space rescue capabilities. The two spaceships opened a hatch and the commanders Thomas P. Stafford and Aleksei Leonov shook hands. The two crews exchanged gifts, thus honoring the first meeting of such kind. Although it was during the Cold War and the two superpowers were adversaries, they celebrated the achievement and were later congratulated by the United Nations Secretary-General Kurt Waldheim. The mission was praised as a token of cooperation and peace.