Professor Ernst Hjalmar Waloddi Weibull (1887 – 1979) was a Swedish engineer and mathematician. He was a professor at the Royal Institute of Technology in Stockholm from 1924 to 1953. He is known for the so-called Weibull distribution, which is a model for statistical probability calculations for technical failures based on material properties. He was also a professor at Columbia University and wrote a large number of papers on strength and material fatigue for the United States Air Force and NASA. Much of his work laid the foundation for the design of spacecraft and the lunar module. ASME - The American Society of Mechanical Engineers has awarded its prestigious gold medal 95 times since 1920.