On May 29, 2009 the ISS crew began to consist of 6 members for the first time. At that day Soyuz TMA-15 spacecraft with 3 cosmonauts aboard docked with the ISS.
Russian cosmonaut Roman Romanenko, Belgium astronaut Frank De Winne and Canadian astronaut Robert Thirsk arrived to the station to work together with Russian cosmonaut Gennadiy Padalka, American astronaut Michael Barrat and Japanese astronaut Koichi Wakata.
This cover was postmarked at Baykonur Cosmodrome with the Russian "International Space Flight” official post cancellation dated May 27, 2009, the day when Soyuz TMA-15spacecraft was launched.
The cover was delivered to the ISS by the Soyuz TMA-15and cancelled aboard the ISS with all proper board seals dated May 29, 2009, the day when Soyuz TMA-15spacecraft docked to the ISS.