Matryoshka Dolls depicting Expedition 39 Commander Koichi Wakata of the Japan Aerospace Exploration Agency (JAXA), left, Soyuz Commander Mikhail Tyurin of Roscosmos, center, and Flight Engineer Rick Mastracchio of NASA are seen at a welcome ceremony, Wednesday, May 14, 2014 at the Karaganda Airport in Kazakhstan. Wakata, Tyurin and Mastracchio returned to Earth after more than six months onboard the International Space Station where they served as members of the Expedition 38 and 39 crews. Photo Credit: (NASA/Bill Ingalls)