He was appointed to the German national astronaut team in 1990. As backup astronaut for Mir ’92, he served as Crew Interface Coordinator at the Russian mission control centre providing communications between the crew in orbit and the project management and scientists on the ground. After the mission, he returned to Germany as the Deputy Head of DLR’s Astronaut Office. In 1997, he flew into space as part of the second German-Russian mission Mir ’97: he launched into space on Soyuz TM 25 on 10 February 1997 and spent 18 days on the Russian Mir space station. Later he went to ESA, worked in the field of human spaceflight, trained astronauts and was involved in setting up the Columbus Control Center, of which he became the director. Today he teaches space systems at the University of Stuttgart.