X-ray data from Rosalind Franklin was key to discovering DNA’s double-helix structure

Rosalind Franklin was the long-overlooked contributor to discovering DNA's structure

Though James Watson, Francis Crick, and Maurice Wilkins are credited with discovering the DNA double helix, it incorporated Rosalind Franklin's unpublished data. Photo 51, her famous DNA image, took more than 100 hours to produce and a year’s worth of analysis to interpret.

Rosalind Franklin’s work led to Nobel Prize-winning discoveries in DNA and virology

Her X-ray diffraction imaging helped uncover the structure of DNA, which earned James Watson, Francis Crick, and Maurice Wilkins a Nobel Prize. The same techniques enabled virus imaging, contributing to Aaron Klug's Nobel Prize in chemistry.

The woman erased from the DNA breakthrough

Rosalind Franklin captured “Photo 51,” the key to DNA’s double helix. Her data, shared without her knowledge, helped Watson and Crick win a Nobel. She never got the prize, but today, her role in unlocking life’s blueprint is finally recognized.

Watson and Crick revealed DNA's double-helix structure using others' key findings

Their 1953 model, made from cardboard cutouts, explained how DNA stores genetic information through base pairing. Rather than experimenting and collecting their own data, they incorporated patterns and data from other scientists through trial and error.

Photo 51's distinct 'X' pattern and spacing provided data to validate DNA's model

Rosalind Franklin and Raymond Gosling captured the photo after bombarding DNA fibers with X-rays and observing how the beams were deflected. The photo had a 62-hour exposure time and indicated a helical structure for DNA.

Watson's book was described as misleading when detailing Franklin's role in DNA

Despite working together to win the Nobel Prize for their discovery of the structure of DNA, Francis Crick and Maurice Wilkins objected to the publication of James Watson's account of DNA's discovery. Those involved describe how he villainized Rosalind Franklin and downplayed her work.

Nature simultaneously published three papers on DNA—only the first made history

Papers by Watson and Crick, Wilkins, and Franklin were fast-tracked without peer review, and their order was arranged between lab heads and editors. Franklin's appeared last, making her paper read as though supporting Watson and Crick—because they'd already incorporated her data before it was published.

Explore a 3D model of the experimental setup Rosalind Franklin used to take Photo 51

To capture the X-ray diffraction image of DNA from the thymus of a calf, Franklin built a humidity-controlling camera to isolate the B form of DNA. The exposure lasted 60 hours and produced a cross pattern, indicating a helical structure.

Beyond DNA, Franklin's legacy extends into modern virology and steel production

While remembered for her critical but under-credited role in uncovering parameters for the structure of DNA, Rosalind Franklin made significant contributions across coal chemistry and virus structure. Her research helped improve fuel efficiency, wartime protective equipment, and foundational knowledge in molecular biology.

Rosalind Franklin uncovered the molecular structure of the tobacco mosaic virus

Franklin's work revealed the role of ribonucleic acid in virus infectivity, contributing to a foundational understanding of genetics and virology. Her molecular model of the virus was featured as the centerpiece at the 1958 Brussels World's Fair.

English chemist Rosalind Franklin (1920 - 1958) on the importance of science

"Science and everyday life cannot and should not be separated. Science, for me, gives a partial explanation of life."

Bacteria helped scientists realize that DNA was the hereditary molecule, not proteins

Until the mid-1900s, most scientists believed genes were made of proteins, which were known to act as enzymes, hormones, and other chemicals that mediated an organism's traits. The Avery-MacLeod-McCarty and that benign bacteria could be made lethal, where the inherited factor that caused bacterial transformation contained DNA.

X-ray diffraction reveals atomic structures by analyzing how crystals scatter X-rays

X-ray diffraction involves rotating a crystal in an X-ray beam while a detector captures the resulting diffraction patterns, which depend on the crystal’s internal structure. The mathematical principles behind the technique won the 1915 Nobel Prize and improved crystallography.

Watch how Sanger sequencing kickstarted the first generation of DNA sequencing

Sanger sequencing is a foundational DNA sequencing technology developed in 1977. The Nobel Prize-winning discovery uses fluorescent dyes at the end of DNA chains, which are sorted by length through electrophoresis, to determine the order of nucleotide bases.

The structure of DNA helices comes in three major varieties

The hereditary molecule can take the form of A-DNA, B-DNA, or Z-DNA based on environmental conditions such as ion concentration and humidity—a characteristic identified by Rosalind Franklin. A-DNA is the shortest and widest of the three, while Z-DNA is the longest and narrowest. B-DNA—the most common variety in living cells—is the intermediate.

Ernest Rutherford's gold foil and nitrogen experiments revealed nuclear structure

Observing high-angle deflections when alpha particles were fired at gold foil led to an atomic model with a dense, positively charged nucleus. Firing those particles at nitrogen resulted in the emission of hydrogen nuclei—protons—leading to the discovery of the subatomic particle.

All publicly available DNA sequences are available at GenBank

The National Institutes of Health's database stores comprehensive, annotated DNA sequences as part of the International Nucleotide Sequence Database Collaboration. It encourages unrestricted data access within the scientific community while allowing submitters to retain intellectual property rights over their data.

DNA computing allows for storage and processing of massive amounts of data

Although costly and less efficient for simpler tasks, as of 2025, DNA could hold 455 exabytes of data with near limitless parallel computation potential in small data centers. Every movie ever made would fit inside the volume of a single sugar cube.

The Golden State killer case spotlights how genetic testing can affect your—and your relatives'—privacy

Police managed to use consumer DNA test results to close a case 32 years after a killer was believed to have committed at least 12 murders and 50 rapes. Their "smoking gun": They compared a DNA sample from the crime scene to genetic data relatives had shared on an open-source genealogy database. The suspect was caught after investigators explored family trees on this database and connected the dots from over 100 distant relatives who had some percentage of DNA that matched the killer. (Some users may encounter a paywall.)

A student researcher working on the Human Genome Project shares their perspective

In a conversation with Ewan Birney, Director of the European Bio-informatics Institute, he discusses what it was like to be a PhD student working on the Human Genome Project in the months before the draft announcement and its impact on him and the field of genetics.

Homology-directed repair is the DNA repair method used by cells

Environmental factors like X-ray exposure may break a strand of DNA, but cells can use a sister strand to patch the damage. Scientists exploit this system by introducing custom DNA templates, which cells use instead to make repairs.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Pierre Curie's knowledge of electromagnetism helped decipher radioactivity

Alongside his brother, he studied electric fields in crystals and the magnetic properties of substances, which required the construction of delicate electrometers. He would use this apparatus with Marie Curie to measure radioactive emissions and the presence of undiscovered radioactive elements.

The 'Penicillin Girls' made mass production possible

In Oxford during the early 1940s, six female technicians—later dubbed the “Penicillin Girls”—worked long hours tending mold cultures and extracting tiny amounts of penicillin.

Validation of the greenhouse effect may have been misattributed

Although Irish physicist John Tyndall showed in 1859 that water vapor and carbon dioxide could absorb and radiate infrared radiation, experiments by American scientist Eunice Foote three years earlier identified the same phenomenon for light in general. Historically overshadowed, her work was rediscovered by female historians over a century later.

A timeline of human fossil discoveries

A key part of writing a coherent story about our origins is finding and identifying the remains of our ancestors and understanding their significance. Scientists will not always agree on identifications and opinions will change as new find are made and new ways of studying them are developed.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Against his wishes, Albert Einstein's brain was removed before his cremation, and the pathologist responsible stored it for decades in mason jars within a beer cooler.

The story of Dollree Mapp, whose legal challenge over her 1957 conviction for possessing "obscene material" led to a major strengthening of the Fourth Amendment

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

English mathematician Ada Lovelace wrote the first computer algorithm a century before computers existed and hypothesized that computing devices would one day be able to compose music—foreseeing the generative AI systems of today.

The Mona Lisa's celebrity status and repeated restorations have obscured what made the painting so revolutionary for its time

Meet the 56 signers of the Declaration of Independence—most of whom didn't put pen to paper until August 2, 1776—and see their original signatures.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

A researcher recently discovered an interview from 1967 between groundbreaking journalist Joan Didion and the Grateful Dead, years before the band became an institution.

Legendary architect Frank Lloyd Wright designed the SC Johnson headquarters in Wisconsin, aiming to make a cathedral-like workplace

Objects can be 3D printed with light by projecting 2D computerized tomography (CT) scans onto rotating cylinders of resin, which solidify upon exposure.

Ebola is a filovirus, meaning it resembles a thread under a microscope, though it sometimes twists and can resemble a bowl of spaghetti.

During the French Revolution, a botanist's letter asking about "dear Rhus" (poison ivy) was intercepted, leading authorities to suspect he was conspiring with the Russians.

The Beatles' US label rejected the band's first two singles, 'Please Please Me' and 'From Me to You,' with one executive calling the band 'dead in the water.'

A small portion of The Winstons' 'Amen, Brother,' an obscure '60s gospel record, is the basis for thousands of hip-hop tracks, making it one of the most sampled records ever that's informally known as 'the Amen break.'

A Yale student wrote a profound essay about the consulting industry's influence on elite college students that was published in a book of her writing after she died in a post-graduation car accident.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

The Dracula character, now seen as the vampire archetype, was inspired by a seafood-induced nightmare its creator experienced.

Brandi Chastain, the star of the 1999 US victory over China in the 1999 Women's World Cup, was a last-second choice to take the penalty kick that sealed the victory.

Search a massive database of over 4 decades of clues from the TV quiz show 'Jeopardy!'

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people