Soyuz 39 was the 15th mission to visit the Salyut 6 space station and carried the the EP-9 crew, which visited the long-duration Soyuz T-4 resident crew. The mission began on March 22, 1981, 14:58, launching Commander Vladimir Dzhanibekov and Research Cosmonaut Jügderdemidiin Gürragchaa, the first Mongolian cosmonaut, into orbit. They docked with the station the next day. During their 7-day stay on the station, EP-9 crew conducted Earth observation, material, medical and other experiments, including cosmic radiation research. The mission concluded with a safe landing back on Earth on March 30, 1981, 11:40:58 UTC.