 He was joined by NASA astronaut Jeanette Epps and Mark Vande Hei as well as ESA astronaut Thomas Pesquet during the nine-day mission.In 2016 he served as part of the 2016 European Space Agency's Cooperative Adventure for Valuing and Exercising human behaviour and performance Skills (CAVES) expedition.Where he spent two weeks underground in caves alongside NASA astronauts Ricky Arnold and Jessica Meir, CNSA taikonaut Ye Guangfu, Roscosmos cosmonaut Sergei Korsakov and ESA astronaut Pedro Duque in order to simulate spaceflight conditions.