Who flew on more Space Shuttle missions, meteorologist Piers Sellers or chemical engineer Lodewijk van den Berg?
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.
Frank L. Culbertson Jr. Frank Lee Culbertson Jr. (born May 15, 1949) (Capt, USN, Ret.) is an American former naval officer and aviator, test pilot, aerospace engineer, and NASA astronaut. He served as the Commander of the International Space Station for almost four months in 2001 and was the only American not on Earth when the September 11 attacks occurred. He is currently a President of The Space Systems Group at Orbital ATK. Mr. Culbertson is responsible for the execution, business development and financial performance of the company’s human spaceflight, science, commercial communications, and national security satellite activities, as well as technical services to various government customers. These include some of Orbital’s largest and most important programs such as NASA’s Commercial Resupply Services (CRS) initiatives to the International Space Station (ISS) as well as various national security-related programs.