Soyuz 35 was a 1980 Soviet crewed space flight to the Salyut 6 space station. It was the 10th mission to and eighth successful docking at the orbiting facility. The Soyuz 35 crew were the fourth long-duration crew to man the space station.
Cosmonauts Leonid Popov and Valery Ryumin spent 185 days in space, setting a new space endurance record. Ryumin had completed a previous mission only eight months before. They hosted four visiting crews, including the first Hungarian, Cuban and Vietnamese cosmonauts.The Soyuz 40 mission was a 1981 Soviet crewed spaceflight and the final flight of the Soyuz 7K-T spacecraft. It was a collaboration between the Soviet Union and Romania.