Bidspirit auction | Cosmonaut Vladimir Aleksandrovich Dzhanibekov signed

Cosmonaut Vladimir Aleksandrovich Dzhanibekov signed vintage Russian Space FDC. Dzhanibekov served on five space missions: Soyuz 27/Soyuz 26 (launch/return), Soyuz 39, Soyuz T-6, Soyuz T-12, and Soyuz T-13. He accrued 145 days, 15 hours, and 56 minutes in space over these five missions. He had also performed two EVAs with the total time of 8 hours and 35 minutes. In 1985 he demonstrated stable and unstable rotation of a T-handle nut from the orbit, subsequently named the Dzhanibekov effect. The effect had been long known from the tennis racket theorem, which says that rotation about an object's intermediate principal axis is unstable while in free fall. 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 time docked to the station, the crew performed joint Soviet-French experiments, including cardiovascular echography, alongside the station's resident crew.