Former Caltech astronomy professor Maarten Schmidt, best known for discovering quasars, dies at 92

Maarten Schmidt, a former Caltech professor best known for discovering quasars, died this month at his home in Fresno. He was 92.

Schmidt died on Sept. 17, Caltech officials announced. Schmidt had joined Caltech in 1959 as an associate professor of astronomy, becoming a full professor in 1964. He also served as an institute professor in 1981, ultimately retiring as a Moseley professor in 1996. He also served as the executive officer for astronomy, chair of the Division of Physics, Mathematics, and Astronomy; and director of the Hale Observatories.

According to Caltech, Schmidt is best known for his discovery of quasars and his measurement of their great distances from Earth. Thousands of quasars have been identified since Schmidt's ground-breaking realization in 1963 that a "quasi-stellar object" was the core of a forming galaxy 3 billion light-years away as he studied the light spectra of radio sources. The objects are visible from Earth today because of the time it takes for light to travel such enormous distances, and Caltech says Schmidt's work gave astronomy new, deep insight into the history of the universe.

Schmidt was born in 1929 in the Netherlands, earning his bachelor's and master's degrees from the University of Groningen. He earned a PhD from Leiden University, and a Doctor of Science degree from Yale in 1966. Schmidt went on to do postdoctoral work at the Mount Wilson and Mount Palomar observatories for two years as a Carnegie Fellow, then returned to the University of Leiden for a year before moving to the United States.

He has received several awards and honors, including the Kavli Prize for Astrophysics, the Bruce Medal, the James Craig Watson Medal, the Gold Medal of the Royal Astronomical Society, the Helen B. Warner Prize, and was on the cover of Time magazine on March 11, 1966.

Schmidt is survived by his three daughters, Anne, Marijke, and Elizabeth.