CAVES, an acronym for Cooperative Adventure for Valuing and Exercising human behaviour and performance Skills, is a European Space Agency astronaut training course in which international astronauts train in a space-analogue cave environment. Designed at the European Astronaut Center, the course aims to prepare astronauts for safe and efficient long duration spaceflight operations by means of a realistic scientific and exploration mission within a multicultural, ISS-representative team.

Randolph James "Komrade" Bresnik is a retired officer in the United States Marine Corps and an active NASA astronaut. A Marine Aviator by trade, Bresnik was selected as a member of NASA Astronaut Group 19 in May 2004. He first launched to space on STS-129, then served as flight engineer for Expedition 52, and as ISS commander for Expedition 53.