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Nier inducted into MST Hall of Fame

Professor Al Nier in 1940 with his mass spectrometer
Professor Al Nier in 1940 with his mass spectrometer.

On November 3, 2010 the late Professor Alfred O. C. Nier was inducted into the Minnesota Science and Technology Hall of Fame. Nier was honored for his development and application of mass spectrometry, which most famously included isolating the first pure sample of the fissionable isotope Uranium-235 in Tate Lab in 1940. A St. Paul native, Nier was a University of Minnesota alumnus (Ph.D., Physics - 1936), a faculty member for more than forty years, and physics chair from 1953 until 1965.

Nier was a member of the National Academy of Sciences and was selected as one of the University's first Regents Professors in 1966.

Nier's work on the Manhattan Project, which developed the first nuclear weapons during World War II, earned a place for his mass spectrometer, a large C-shaped glass tube, in the Smithsonian Institution. After the war, Nier continued to develop mass spectrometry for many applications, and in 1968 he joined the Viking space mission to explore the Martian surface and probe for possible signs of life. Nier designed the miniature mass spectrometers on the Viking landers that were used to analyze the atmosphere of Mars.

Nier's contributions and fame extend beyond physics and astrophysics. In 1935, he discovered the radioactive isotope Potassium-40 and later proved that Argon-40 was a product of its decay. These discoveries led to the development of Potassium-Argon dating, which remains one of the most powerful tools for determining the age of the Earth. Nier's contributions in the field of geophysics earned him the Arthur L. Day Medal in 1956 and there is a geophysics scholarship in his name as well.

The Science and Technology Hall of Fame is the joint effort of the Minnesota High Tech Association and the Science Museum of Minnesota. Its purpose is to honor the achievements of Minnesotans in the field of science and technology. The Hall of Fame is an honor reserved for the "best of the best" from the State of Minnesota. Nier was one six people inducted in 2010.