Luyten died in 1994.
From the description of Response to History of Modern Astrophysics Survey, 1980. (Unknown). WorldCat record id: 79918246
Willem J. Luyten was born on 7 March 1899 in Semarang, Dutch East Indies (now Java, Indonesia). He earned his B.A. in 1918 from the University of Amsterdam and his M.A. in 1920 and Ph.D. in 1921 from the University of Leiden, Holland (now Leiden University, the Netherlands). Before coming to the University of Minnesota, Dr. Luyten was a fellow at the University of California (1921-1923) and astronomer and assistant professor at the Harvard Observatory and Harvard University (1923-1930). In 1930, Dr. Luyten became an assistant professor and chair of the astronomy department at the University of Minnesota. He was promoted to associate professor in 1934 and professor in 1938, while remaining as department chair. Dr. Luyten retired from the University of Minnesota as professor emeritus in 1967.
Dr. Luyten was an internationally recognized expert in measuring stellar motion and detecting dying stars, which are known as white dwarfs. By the mid 1950s, Dr. Luyten and his associates had located over 80% of the then known white dwarfs stars. In 1959, Dr. Luyten discovered the most distant celestial object in the sky at that time, known as a blue star. In 1963, Dr. Luyten was credited with finding the smallest and densest known star in the Universe. Even though he officially retired in 1967, Dr. Luyten continued to conduct research well into the 1980s. In 1980, he discovered asteroid No. 1, 964, which is named after him. Dr. Luyten was a prolific writer and publisher and he won many awards over his 50-plus year career as an astronomer, including the James Craig Watson medal, the oldest medal of the National Academy of Sciences (1964). Willem Luyten died on 21 November 1994.
From the guide to the Willem J. Luyten papers, 1920s-1980s, (University of Minnesota Libraries. University of Minnesota Archives [uarc])