Rosalind Franklin -- X-Ray Crystallographer and DNA Pioneer (1920-1958)
Rosalind Elsie Franklin (1920-1958) was an English chemist and X-ray crystallographer whose work was central to the discovery of the molecular structure of DNA. Her X-ray diffraction image known as Photo 51 provided critical evidence for the double helix structure, which was used by James Watson and Francis Crick without her knowledge or permission. Franklin also made seminal contributions to the understanding of coal, graphite, and viruses. Her role in the DNA discovery went largely unrecognized during her lifetime, leading to a contested historical legacy about scientific credit and gender bias in science.
Events
Birth in London
Rosalind Elsie Franklin is born into an affluent and influential British Jewish family. Her father, Ellis Franklin, is a merchant banker who teaches at the Working Men's College. Her uncle is Herbert Samuel, Home Secretary and the first Jewish member of the British Cabinet. The family helps settle Jewish refugee children from Nazi Europe through the Kindertransport program.
Education at St Paul's Girls' School
Franklin enters St Paul's Girls' School in Hammersmith, one of the few girls' schools in London that teaches physics and chemistry. She excels in science, Latin, and sports, winning annual awards and developing her fluency in French and German. She passes her matriculation in 1938 with six distinctions, winning a university scholarship. Her father asks her to give the scholarship to a refugee student instead.
Cambridge University and Wartime Service
Franklin enters Newnham College, Cambridge to study chemistry within the Natural Sciences Tripos. She graduates in 1941 with second-class honours (Cambridge did not award degrees to women until 1947). During World War II, she serves as an Air Raid Precautions warden while working as an assistant research officer at the British Coal Utilisation Research Association (BCURA), studying the porosity and structure of coal.
PhD in Physical Chemistry for Coal Research
Franklin's wartime research on coal earns her a PhD from Cambridge University. She discovers the relationship between the fine constrictions in coal pores and the permeability of the porous space, classifying coals by their performance for fuel and wartime gas mask production. Her coal research remains cited in the field for decades.
Postdoctoral Research in Paris -- Becoming a Crystallographer
Franklin moves to Paris to work as a postdoctoral researcher (chercheur) under Jacques Mering at the Laboratoire Central des Services Chimiques de l'Etat. She becomes an accomplished X-ray crystallographer, applying the technique to analyze the structure of carbons. Her time in Paris is among the happiest of her life; she thrives in the collaborative French research environment and becomes fluent in the language.
Joins King's College London and Begins DNA Research
Franklin joins King's College London as a research associate in the Medical Research Council's Biophysics Unit led by John Randall. She is assigned to work on DNA structure using X-ray crystallography, though a miscommunication between Randall and her laboratory colleague Maurice Wilkins leads Wilkins to believe Franklin is his assistant rather than an independent researcher. This misunderstanding creates a tense working relationship.
Photo 51 -- The Key X-Ray Diffraction Image
Franklin and her graduate student Raymond Gosling produce the sharpest X-ray diffraction image of DNA ever captured -- Photo 51. The image reveals a clear X-shaped pattern indicating a helical structure and provides measurable dimensions of the helix. Franklin meticulously analyzes the data, determining key parameters of the DNA molecule including the spacing between nucleotides and the number of chains.
Moves to Birkbeck College -- Virus Research
Franklin leaves King's College London due to the difficult working relationship with Wilkins and Randall. She moves to Birkbeck College to work under John Desmond Bernal, leading pioneering research on the molecular structure of viruses using X-ray crystallography. Her team makes significant progress on understanding the structure of tobacco mosaic virus (TMV).
The Double Helix Model Published -- Using Franklin's Data
James Watson and Francis Crick publish their model of the DNA double helix in Nature, based in part on Franklin's Photo 51 and crystallographic data. Maurice Wilkins had shown Franklin's photo and data to Watson, without Franklin's knowledge or permission. Watson and Crick's paper acknowledges being "stimulated by a knowledge of the general nature of the unpublished experimental results and ideas" of Franklin and Wilkins. Franklin publishes her own paper in the same issue of Nature, supporting the helical structure.
Death from Ovarian Cancer
Franklin dies of ovarian cancer at age 37, likely caused or accelerated by her prolonged exposure to X-ray radiation in an era before strict safety protocols. She is buried at Willesden United Synagogue Cemetery. On the day before her death, she was to unveil the structure of tobacco mosaic virus at an international fair in Brussels. Her colleague Aaron Klug continues her virus research and wins the Nobel Prize in Chemistry in 1982.
Posthumous Recognition and Reassessment
Watson, Crick, and Wilkins receive the Nobel Prize in Physiology or Medicine for the discovery of the DNA double helix. The Nobel Prize is not awarded posthumously, so Franklin is ineligible despite her essential contribution. In the decades that follow, historians and scientists increasingly recognize Franklin's role, sparking debates about scientific credit, gender discrimination, and whether she should have shared the prize. Numerous institutions, awards, and the Mars rover Rosalind Franklin are named in her honor.