Photo 51

1952 X-ray diffraction photograph of DNA

Photo 51 is a 1952 X-ray based fiber diffraction image of a paracrystalline gel composed of DNA fiber taken by Rosalind Franklin's PhD student Raymond Gosling at King's College London, while working in Sir John Randall's group; Maurice Wilkins later shared the image with James Watson without their permission. The image was tagged "photo 51" because it was the 51st diffraction photograph that Gosling had taken.

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