I only spotted this 2026[1] paper this evening. And I believe that it dismantles some persistent misapprehensions about her research.
Rosalind Franklin recognised the helical structure of DNA’s B form and calculated key dimensions in May 1952, months before James Watson even saw the photograph he made famous. The familiar story that she produced the evidence but failed to understand it collapses against her laboratory records.
Her scientific judgement did not require Watson’s retrospective permission.
This 2026 study by historian Alistair Sponsel and crystallographer Brian Sutton explains what that story has missed. The crucial photograph for understanding Franklin’s own discovery is Photograph 49. Photograph 51 was her deliberate, better-composed record of a result she had already analysed.
She had already done the analysis
On the morning of 2 May 1952, Franklin and her PhD student Raymond Gosling completed Photograph 49. Franklin immediately analysed its unusually sharp diffraction pattern. Her notes calculated a repeat of 34 ångströms, or 3.4 nanometres, along the molecule and ten layers of nucleotide bases per turn of the helix. She was interpreting molecular structure, not merely operating a camera.
The image had a practical defect: the film holder was misaligned, cropping part of the pattern. That evening, Franklin began the exposure that would produce Photograph 51, using the same DNA specimen and conditions, with the holder centred properly. She knew which features the new image should contain and specified them in advance.
Later commentators treated the absence of fresh analysis beneath that notebook entry as evidence that she had ignored the result. Sponsel and Sutton show why this is backwards. The analysis was already recorded under Photograph 49. Photograph 51 documented it more clearly. Turning a competent decision to repeat an exposure into evidence of intellectual failure takes quite some nerve.
Her subsequent concentration on DNA’s A form also had a scientific purpose. Franklin had distinguished the A and B forms and wanted to understand both. The crystalline A form offered richer diffraction data for detailed analysis. Hindsight made the B form the winning destination; it did not make her research programme irrational.
The helix and the double helix
Precision matters here. Recognising a helix and measuring its dimensions does not, by itself, establish the number of chains or complementary base pairing. By 10 February 1953, Franklin’s notebook explicitly examined “evidence for [a] 2-chain […] helix”. Watson and Crick subsequently produced the complete, correctly base-paired model, published on 25 April 1953. Franklin and Gosling’s own paper appeared in the same issue.[1][2]
The new study establishes Franklin’s early understanding of the B-form helix and the intellectual work behind its defining evidence. It does not establish her as the first person ever to propose the complete double-helix structure. Her rightful place as a co-discoverer rests on what she actually did. Inflating the claim would give defenders of the old caricature an unnecessary escape route.
How the caricature survived
Watson’s 1968 memoir, The Double Helix, helped establish the damaging version: Franklin was technically capable, emotionally difficult, and unable to grasp the theoretical significance of her own results. She had died in 1958 and could not answer it. Sponsel and Sutton trace how later accounts repeated the supposed failure, even while praising her experimental skill.
That praise has a nasty little trap built into it. Make the woman exceptionally good at producing data, then reserve the intellectual breakthrough for the men who used them. It sounds generous until one notices who has been allowed to think.
Gosling deserves credit for their collaboration. Franklin deserves credit for leading it, designing the experiments, interpreting the results, and deciding how to present them. Replacing one omitted scientist with another would repeat the same shabby accounting.
Franklin’s notebooks record the work. Watson’s memoir records his version of it. For too long, his version was allowed to overrule her evidence.
The record is there. Put Rosalind Franklin back among the discoverers, and retire the patronising fiction that she needed a man to explain her own science.
References
[1] Sponsel, Alistair, and Brian Sutton (2026). Photograph 49 is the Key to Understanding the History of Rosalind Franklin’s DNA Photograph 51. Journal of the History of Biology. Laboratory notebooks, photographs, and apparatus underpin the analysis.
[2] Franklin, Rosalind E., and R. G. Gosling (1953). Molecular Configuration in Sodium Thymonucleate. Nature 171, 740–741. Published 25 April 1953, alongside Watson and Crick’s model and the paper by Wilkins, Stokes, and Wilson.
