The world has lost a mind whose work guides us every day. Gladys West, a pioneering mathematician whose contributions helped make modern GPS possible, has passed away at 95, peacefully on January 2026, surrounded by family and friends. West’s mathematical models of the Earth’s shape became a critical foundation for satellite navigation, allowing precise positioning anywhere on the globe. Her work helps guide everything from airplanes and ships to smartphones and emergency services, though she once joked that she still preferred using paper maps. Born in 1930 in rural Virginia, West grew up in the South, working on her family’s farm and walking miles to a one-room schoolhouse. She originally planned to study home economics, but discovered a love for geometry that led her to pursue mathematics. A scholarship took her to Virginia State College, where she earned her degree and later a master’s in mathematics. In 1956, she joined a U.S. Navy research facility in Dahlgren, Virginia. Over a 42-year career, West worked with early computers to develop algorithms that accounted for the Earth’s irregular shape, gravity, and tidal forces, refinements that were essential for accurate satellite positioning. Without the mathematical groundwork she helped establish, the global navigation systems used today would not function as they do. For most of her career, West’s contributions remained largely unknown outside scientific circles. Later in life, she received major honors, including induction into the U.S. Air Force Hall of Fame and the Prince Philip Medal. She inspired generations of scientists and mathematicians.