Francis Harry Compton Crick OM (June 8, 1916 - July 28, 2004)
According to Wikipedia, Crick "was an English molecular biologist, physicist, and neuroscientist, who is most noted for being one of the co-discoverers of the structure of the DNA molecule in 1953. He, James D. Watson, and Maurice Wilkins were jointly awarded the 1962 Nobel Prize for Physiology or Medicine 'for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material.'
"He was skeptical of organized religion and did not believe existence of God, referring to himself as a skeptic and an agnostic with 'a strong inclination towards atheism.'"