may 1, 1952 - Maurice Wilkins & Rosalind Franklin
In 1950, Maurice Wilkins and Ray Gosling acquired the first clear crystalline x-ray diffraction patterns of DNA fibers. Alec Stokes suggested that the shape of DNA was helical based on the picture. In May 1952, Rosalind Franklin took the famous picture, Photo 51. This validated the helical shape of DNA and showed that the nitrogenous bases were inside the DNA molecule, not on the outside.
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