Gladys West’s satellite work helped create the mathematical model underlying modern GPS.
West was a mathematician and geodesist who worked at the U.S. Naval Weapons Laboratory. Beginning in the 1970s, she used satellite observations and powerful computers to model Earth’s shape and gravitational variations. Her calculations contributed to the precise geodetic models needed to determine locations on a planet that is not a perfect sphere.
West’s work was part of a much larger effort involving many scientists, engineers, satellites, and institutions. GPS itself depends on timing signals from satellites and complex calculations performed by receivers and control systems. West did not invent GPS alone, but her modeling of Earth’s geoid was an important contribution to the accuracy of global positioning. Her role received wider public attention after she was inducted into the U.S. Air Force Space and Missile Pioneers Hall of Fame in 2018.