Prof. Dr. Dr. h.c. Ulrich Hans Walter (born February 9, 1954) is a German physicist/engineer and a former DFVLR astronaut. In 1993, he flew on board the Space Shuttle Columbia on mission STS-55 (Spacelab D-2) as a Payload Specialist. He spent 9 days, 23 hours, and 40 minutes in space. Read more