Question: Ulf Merbold and Lodewijk van den Berg, both flew in ?

full_context: Document 1: Umberto Guidoni: Umberto Guidoni (born in Rome 18 August 1954) is an Italian astrophysicist, science writer and a former ESA astronaut, being the first European to visit the International Space Station. He is a veteran of two NASA space shuttle missions. He was also a Member of the European Parliament (MEP) from 2004 to 2009, elected within the Party of Italian Communists.
Document 2: Wubbo Ockels: Wubbo Johannes Ockels (28 March 1946 – 18 May 2014) was a Dutch physicist and an astronaut of the European Space Agency (ESA). In 1985 he participated in a flight on the space shuttle Challenger, STS-61-A, making him the first Dutch citizen in space. After his astronaut career, Ockels was professor of "Aerospace for Sustainable Engineering and Technology" at the Delft University of Technology.
Document 3: Ulf Merbold: 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.
Document 4: Sigmund Jähn: Sigmund Werner Paul Jähn (born 13 February 1937) is a German cosmonaut and pilot, who in 1978 became the first East German (and German native) to fly in space as part of the Soviet Union's Interkosmos programme.
Document 5: Christer Fuglesang: Arne Christer Fuglesang (] ) (born March 18, 1957 in Stockholm) is a Swedish physicist and an ESA astronaut. He was first launched aboard the STS-116 Space Shuttle mission on December 10, 2006, at 01:47 GMT, making him the first Swedish citizen in space.
Document 6: Jack Swigert: John Leonard "Jack" Swigert Jr. (August 30, 1931 – December 27, 1982) was an American test pilot, mechanical and aerospace engineer, United States Air Force pilot, and NASA astronaut, one of the 24 people who have flown to the Moon.
Document 7: L.W.C van den Berg: Lodewijk Willem Christiaan van den Berg (October 19, 1845 – March 2, 1927), or more commonly known as L.W.C. van den Berg, was a Dutch oriental scholar in the Dutch colonial era famous with his research on Arab Indonesians of Hadhrami descent, which was the first detailed research of its kind in the world at the time.
Document 8: Ulrich Walter: Prof. Dr. Ulrich Hans Walter (born February 9, 1954) is a German physicist/engineer and a former DFVLR astronaut.
Document 9: Space Shuttle Challenger: Space Shuttle "Challenger" (Orbiter Vehicle Designation: OV-099) was the second orbiter of NASA's space shuttle program to be put into service following "Columbia". The shuttle was built by Rockwell International's Space Transportation Systems Division in Downey, California. Its maiden flight, STS-6, started on April 4, 1983. It launched and landed nine times before breaking apart 73 seconds into its tenth mission, STS-51-L, on January 28, 1986, resulting in the death of all seven crew members, including a civilian school teacher. It was the first of two shuttles to be destroyed in flight, the other being "Columbia" in 2003. The accident led to a two-and-a-half year grounding of the shuttle fleet; flights resumed in 1988 with STS-26 flown by "Discovery". "Challenger" itself was replaced by "Endeavour" which was built using structural spares ordered by NASA as part of the construction contracts for "Discovery" and "Atlantis".
Document 10: Gentry Lee: Bert Gentry Lee (born 1942) is the chief engineer for the Planetary Flight Systems Directorate at the Jet Propulsion Laboratory and also a science fiction writer. He had engineering oversight responsibility for the twin rover missions to Mars that landed in January 2004, the Mars Reconnaissance Orbiter (MRO) in 2006, and the Deep Impact and Stardust missions. He was also the chief engineer for the Galileo project from 1977–1988 and director of science analysis and mission planning during the Viking projects.
Document 11: Albert Jan van den Berg: Albert Jan van den Berg (born 14 June 1949 in Amsterdam) is a founding partner of Hanotiau & van den Berg in Brussels (since 2001), a Emeritus Professor of Law at the Erasmus University, Rotterdam, a visiting Professor at Georgetown University Law Center, Washington DC and at the University of Tsinghua School of Law, Beijing and a member of the Advisory Board and Faculty of the Geneva Master of Laws in International Dispute Settlement (MIDS), Geneva.
Document 12: Lodewijk van den Berg: Lodewijk van den Berg (] ; born March 24, 1932) is a Dutch American chemical engineer, specializing in crystal growth, who flew on a 1985 Space Shuttle "Challenger" mission as a Payload Specialist.
Document 13: Klaus-Dietrich Flade: Klaus-Dietrich Flade (born August 23, 1952) is a German pilot and former German Aerospace Center astronaut who visited the Mir space station in 1992 aboard the Soyuz TM-14 mission, returning to Earth a week later aboard Soyuz TM-13.
Document 14: Janwillem van den Berg: Janwillem van den Berg (26 November 1920 in Akkrum – 18 October 1985 in Groningen) was a Dutch speech scientist and medical physicist who played a major role in establishing the myoelastic-aerodynamic theory of voice production. The most notable aspect of van den Berg's theory is its impact on modern speech science in providing a foundation for modern models of vocal fold function.
Document 15: Hans Schlegel: Hans Wilhelm Schlegel (Überlingen, 3 August 1951) is a German physicist, an ESA astronaut, and a veteran of two NASA Space Shuttle missions.
ground_truth: space