Who was the project scientist for the Voyager mission?

Edward Stone was the project scientist for the Voyager mission.

Stone became Voyager's project scientist in 1972, several years before the twin spacecraft launched in 1977. He helped coordinate the mission's scientific priorities, including decisions about observation targets, instrument operations, and the spacecraft trajectories. He also became the mission's best-known public spokesperson as Voyager returned discoveries from the outer planets.

Under Stone's scientific leadership, Voyager documented active volcanoes on Jupiter's moon Io, explored Saturn's rings and Titan, and became the first mission to visit Uranus and Neptune. After the planetary encounters ended, Stone helped secure support for the extended Voyager Interstellar Mission, allowing the probes to continue studying the space beyond the heliosphere.

Stone was also director of NASA's Jet Propulsion Laboratory from 1991 to 2001 and remained associated with Voyager for five decades before retiring from the project in 2022. Carl Sagan was a prominent Voyager scientist and communicator, but he was not the mission's project scientist.