After two years of hammering out details and wording, President Nixon and Soviet Premier Alexei Kosygin sign an international agreement to share science and technology between the United States and Soviet Union, including an agreement to mount a joint space mission culminating in the docking of an Apollo spacecraft and a Soyuz spacecraft in Earth orbit in 1975. Both nations’ space agencies begin crew selection and technical preparations for a joint venture that seemed impossible during the Cold War-fueled race to the moon.
With planning already well underway for the Apollo-Soyuz mission which won’t take place until 1975, NASA commissions a study from McDonnell Douglas to explore the feasibility of a follow-up to the international space mission, possibly involving joining the backup of the Skylab space station (known as “Skylab B”) and a yet-to-be-launched Soviet Salyut space station at some point in the latter half of the 1970s, effectively creating a joint international space station. Although the study goes so far as to specify issues of concern regarding the structure of the two stations and their respective standard atmospheric pressures, the recommendations are shelved pending the outcome of the Apollo-Soyuz flight. Significant political developments in the late 1970s will prevent the idea of an international station from moving forward for at least a quarter century.
The final launch of an Apollo spacecraft takes place as the last Saturn rocket carries the American component of the Apollo-Soyuz Test Project into orbit. A cooperative international mission intended to see the Apollo capsule dock with a Soviet-launched Soyuz, the ASTP will be the last Apollo flight as the push toward the reusable Space Shuttle takes over NASA’s resources and planning. Aboard the Apollo command/service module are Commander Thomas Stafford, command module pilot Vance Brand, and docking module pilot Deke Slayton, the last of the seven original Mercury astronauts to reach space (heart conditions have prevented him from taking part in a mission until now). Soyuz 19, carrying cosmonauts Alexei Leonov and Valery Kubasov, lifts off a few hours earlier.
The last Apollo spacecraft to fly makes history by docking with a Soviet-launched Soyuz spacecraft in orbit, allowing the crews to visit each other and conduct joint scientific experiments. The first docking of the Apollo-Soyuz Test Project is hailed as a major development in international relations as well as spaceflight, though it will be 20 years before the feat is repeated. Plans for a second Apollo-Soyuz flight the following year are scuttled due to budget concerns, and the need to commence work on converting NASA’s launch facilities for future shuttle launches rather than further Apollo launches.
The “age of Apollo” comes to an unbreathable end in an incident during the return of the final Apollo spacecraft. Returning from their successful Apollo-Soyuz Test Project flight, astronauts Thomas Stafford, Deke Slayton and Vance Brand are exposed to fumes from their vehicle’s own reaction control thrusters, thanks to the thrusters firing after the capsule’s air vents open during descent toward the Pacific Ocean. Brand reportedly passes out momentarily due to the toxic fumes. All three astronauts are hospitalized for two weeks in Hawaii.
With the 1972 agreement having resulted in the successful Apollo-Soyuz Test Project, the United States and the Soviet Union formally renew the Space Cooperation Agreement. As an immediate goal to build on Apollo-Soyuz, both countries hold tentative discussions about docking the American Space Shuttle (which, it is still assumed, will be in space before the 1970s are out) and a Soviet Salyut space station. Though the shuttle’s first flight is still being delayed, the biggest hurdle will prove to be international relations, specifically a renewed chilling of the Cold War thanks to the Soviet Union’s 1979 invasion of Afghanistan.
The surviving Apollo-Soyuz Test Project astronauts and cosmonauts gather at the Stafford Air & Space Museum (founded by Apollo-Soyuz commander Thomas Stafford) in Weatherford, Oklahoma to mark the 30th anniversary of the first international manned spaceflight. (theLogBook.com’s webmaster is in attendance.)