Helen S. Hopfield

Helen Hopfield (, 1899 – January 16, 1989) was an American physicist who worked at the Applied Physics Laboratory. Her contributions in atmospheric physics and orbital mechanics allowed for more precise satellite-tracking technologies. The Hopfield model to study the troposphere is named in her honor.

She was the wife of spectroscopist John J. Hopfield, also a physicist known for his research on ultraviolet spectroscopy, and the mother of John Joseph, Jr., a winner of the Nobel Prize in Physics.

Biography

Education Hopfield was born in Fort Atkinson, Wisconsin. She completed her higher education with distinction in her A.B. degree in physics from Colorado College in 1921 and an M.A. in physics from Mount Holyoke College in 1924. Her early academic career included teaching positions in physics and mathematics at Winthrop College in South Carolina and a teaching fellowship at the University of California, Berkeley from 1926 to 1928.

Career Hopfield joined the Applied Physics Laboratory (APL) at Johns Hopkins University in 1943, where she remained a key figure until her retirement in 1976, She is credited for developing the Hopfield model, which calculates zenith tropospheric delays based on the relationship between refractive indices at the Earth’s surface and at a given height.

Family Hopfield was married to John J. Hopfield Sr., a physicist known for his discovery of several ultraviolet bands in the solar spectrum.

Hopfield died on January 16, 1989. She was survived by her three children.