Japanese astronaut Koichi Wakata flew to the station on STS-119 and served as flight engineer for Expeditions 18, 19 and 20. Wakata will serve as Expedition 38 flight engineer and become Japan's first station commander during Expedition 39.› Biography →
Rick Mastracchio served as a mission specialist for shuttle missions STS-106, STS-118 and STS-131 which visited the International Space Station. He will be flight engineer for Expedition 38/39.› Biography →
Mikhail Tyurin served as Flight Engineer for Expeditions 3 and Expedition 14. He accumulated a total of 340 days in space including 25 hours and 32 minutes of spacewalk time in 5 spacewalks.› Biography →
Steve Swanson will be Expedition 40 commander. He also served as a mission specialist for two space shuttle missions. Both missions, STS-117 and STS-119, visited the International Space Station.› Biography →
Alexander Skvortsov served as Flight Engineer for Expedition 23 and Commander for Expedition 24 in 2010.› Biography →
Russian cosmonaut Oleg G. Artemyev is flight engineer for Expedition 39/40.