Donald Alfred Gurnett (April 11, 1940 – January 13, 2022) was an American physicist and professor at the University of Iowa who specialized in plasma physics.

[1] Gurnett's research into space plasmas (and his involvement in the development of electronics and measuring devices for space missions) began while he was a student and eventually led to early studies of plasma waves in the Earth's radiation belt (via low-frequency radio waves).

He participated to the Injun satellites program designed and built by researchers at the University of Iowa to observe various radiation and magnetic phenomena in the ionosphere and beyond.

[1] In late August 2012, the radio and plasma-wave instrument designed by Gurnett onboard Voyager 1 confirmed that it had crossed the heliopause.

In addition, he received the Humboldt Prize, with which he was at the Max Planck Institute for Extraterrestrial Physics in Garching (1975/76).