The text on the pin reads:”Joint Space Flight”. Soyuz T-6 was a human spaceflight to Earth orbit to the Salyut 7 space station in 1982. Along with two Soviet cosmonauts, the crew included a Frenchman, Jean-Loup Chrétien. The Soyuz-T spacecraft arrived at Salyut 7 following launch on 24 June 1982 and one day of solo operations. During the T-6 mission’s the crew performed joint Soviet-French experiments, including cardiovascular echography, alongside the station’s resident crew. The mission transported the first French astronaut, Jean-Loup Chrétien, into space. While aboard the station, the resident crew afforded him the opportunity to eject Salyut 7’s weekly bag of waste into space through the station’s small trash airlock.
Interkosmos was a Soviet space program, designed to help the Soviet Union’s allies with manned and unmanned space missions.
The program included the allied east European nations of the Warsaw Pact and other socialist nations like Afghanistan, Cuba, Mongolia, and Vietnam. In addition, pro Soviet nations such as India and Syria participated, and even France and Austria, despite them being capitalist nations.