Dr. Ulf Dietrich Merbold (born June 20, 1941) is the first West German citizen and second German native (after Sigmund Jähn) to have flown in space. He is also the first member of the European Space Agency Astronaut Corps to participate in a spaceflight mission and the first non-US citizen to reach orbit in a US spacecraft. In 1983, he and Byron Lichtenberg became the first Payload Specialists to fly on the shuttle.