Stanton Terry Friedman (July 29, 1934 – May 13, 2019) was a Canadian-American nuclear physicist and professional ufologist widely regarded as one of the most rigorous and prolific civilian UFO researchers of the 20th century. He earned bachelor's and master's degrees in physics from the University of Chicago and worked for 14 years as a nuclear physicist for companies including General Electric, General Motors, Westinghouse, and Aerojet General Nucleonics.

Friedman became the original civilian investigator of the 1947 Roswell incident, beginning his investigation in 1978 after locating key witness Jesse Marcel. His research led to multiple books and documentaries on Roswell and government UFO secrecy. He was a forceful proponent of the extraterrestrial hypothesis and argued that the U.S. government had engaged in a deliberate, sustained program of UFO information suppression he termed "Cosmic Watergate."

Among his most significant contributions was co-authoring Crash at Corona (1992) with Don Berliner, detailing evidence for a 1947 UFO crash retrieval, and Captured! The Betty and Barney Hill UFO Experience (2007) with Kathleen Marden (Betty Hill's niece). He also wrote Flying Saucers and Science (2008) and Top Secret/MAJIC (1996), examining the controversial Majestic 12 documents.

Friedman lectured at over 600 colleges and universities in 50+ countries and appeared on hundreds of radio and television programs. He debated prominent skeptics including Carl Sagan and Philip Klass. His scientific background gave his advocacy unusual credibility within both the research community and public discourse.