Expedition 20 was the 20th long-duration flight to the International Space Station. The expedition marked the first time a six-member crew inhabited the station. Because each Soyuz-TMA spacecraft could hold only three people, two separate launches were necessary: Soyuz TMA-14 launched on 26 March 2009, and Soyuz TMA-15 followed on 27 May 2009.
Soyuz TMA-15 launched from Baikonur Cosmodrome at 10:34 UTC on 27 May 2009. The vehicle docked with the station on 29 May 2009, officially changing the Soyuz TMA-14 crew from Expedition 19 to Expedition 20.
Gennady Padalka was the first commander of a six-member station crew, and the first commander of two consecutive expeditions (Expedition 19 and 20). Nicole Stott was the final expedition astronaut to be launched on the shuttle.
This version of the A-B Emblem patch features the crew members' names.