An X-ray photo labeled '51' gave away DNA's shape without its taker's consent

In May 1952, Rosalind Franklin and student Raymond Gosling captured an X-ray image of DNA fibers so clear its X-shaped pattern all but announced a helix. Colleague Maurice Wilkins showed the image, later called Photo 51, to James Watson without her knowledge, and Watson and Crick used it to help build their double-helix model weeks later. Franklin died in 1958; since Nobel Prizes aren't posthumous, she was never eligible for the 1962 prize shared by Watson, Crick, and Wilkins.

— Rosalind Franklin and Raymond Gosling, Photo 51 — King's College London, May 1952