Rosalind Franklin uncovered the molecular structure of the tobacco mosaic virus

View the model of the tobacco mosaic virus from the 1958 Brussels World's Fair

After she finished analyzing her X-ray diffraction data on DNA fibers, Rosalind Franklin explored plant virus structures. For her work on the TMV, she was invited to build this 5-foot model, modified from earlier versions made of ping pong balls and bicycle handlebar grips.

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.

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 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Crick, and Maurice Wilkins are credited with discovering the DNA double helix, it incorporated Rosalind Franklin's unpublished data.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.

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

Although unpublished, the data reached James Watson and Francis Crick, who worked at another institution. Incorporating her data allowed them to validate their model of DNA, which they published without crediting her.

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.

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.

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.

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.

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."

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.

Exploring carbon compound pore structures contributed to improved gas mask filtration

During World War II, the British Coal Utilisation Research Association sought to improve the efficiency of coal as an energy source and studied the effectiveness of charcoal filters to keep soldiers safe. Rosalind Franklin's research there formed the basis of her PhD and led to five scientific papers.

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.

Explore 3D models of some of the most dangerous viruses, allowing us to understand these and other pathogens in new ways.

View a collection of historical documents about molecular biology's history

The collection features materials related to those involved in the discovery of DNA and provides historical context for the discoveries of RNA, various viruses, and important bioproteins. The items include photographs, business correspondence, manuscripts, and scientific instruments.

Explore a 3D model of the influenza virus

This interactive 3D model reveals the influenza virus’s structure—its outer coat and spike proteins—and compares it with other well-known viruses, offering a clear view of how flu differs from pathogens like HIV or coronaviruses.

See a timeline of landmark discoveries in the field of genetics to gain a better understanding of more than a century of advances.

The foundation for computer viruses was published after its creator's death

In the late 1940s, Hungarian American mathematician, scientist, and engineer John von Neumann gave a series of lectures where he explained the theoretical framework for a computer program that could replicate itself—the von Neumann Universal Constructor. His lectures were later compiled and published in 1966, nine years after his death from cancer.

Explore a technical look at the measles virus and its toll on humanity through the ages.

Oxford scientists turned Fleming’s mold discovery into medicine

In 1939, a team at Oxford—including Howard Florey, Ernst Chain, and Norman Heatley—revived Fleming’s forgotten discovery. Using makeshift equipment like bedpans and milk churns, they purified enough penicillin to prove it could treat deadly infections.

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.

In 1933, the influenza virus was first identified through 'ferret flu' experiments, which proved that the disease was viral—not bacterial.

See colorized mpox virus particles grown in culture at Fort Detrick, Maryland, where high-biosecurity pathogens are studied.

How the 1918 pandemic spurred developments in virology and vaccines

This article provides an in-depth historical account of the 1918 Spanish Flu pandemic, including its impact on the global population and how its occurrence spurred significant advancements in the study of viruses—laying the groundwork for the...

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.

The mosquito's role in the transmission of malaria was confirmed in 1897.

Marie Curie's daughter Irene discovered artificial radioactivity

The discovery continued the family's Nobel legacy by winning the Nobel Prize in Chemistry in 1935 alongside her husband, Frederic Joliot. Their work laid the foundation for the use of radioisotopes in medicine, agriculture, and energy production.

The discovery of the first extremophile and how it revolutionized DNA analysis

While investigating samples taken from within and around the hot springs at Yellowstone National Park, microbiologist Thomas Brock discovered Thermus aquaticus, a microorganism that thrived in hot water. It contained an enzyme called Taq polymerase, a critical molecule in polymerase chain reaction—a molecular photocopier that amplifies genetic signals to improve medical diagnostics.

Marie Curie's research in radioactivity made her the first woman to win a Nobel Prize

Overcoming social and academic barriers, Curie's realization that radiation resulted from an intrinsic property of atoms reframed scientific understanding of the phenomenon. Her subsequent work in discovering two new elements—polonium and radium—earned her a second Nobel Prize.

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.

Mosaic is credited for making the World Wide Web accessible to everyday people—not just scientists—for the first time

Mosaic was a web browser that allowed people to more easily access webpages on the World Wide Web. But unlike previous browsers, Mosaic was a graphical browser, which means it displayed images alongside text. This helped turn the web from a place for scientists into a cultural location that captured people's attention.

A weed from the mustard family facilitated the molecular era of botany

The small genome and rapid growth cycle of Arabidopsis thaliana have made it an ideal organism for genetic studies, with over 100,000 research papers exploring topics such as disease resistance, stress tolerance, and response to light. The first studies were done on plants that grew from seeds saved during the Hungarian Uprising of 1956.

A moldy cantaloupe supercharged penicillin production

In 1943, a moldy cantaloupe found at a market in Peoria, Illinois, yielded a strain that produced six times more penicillin. Though often credited to lab worker “Moldy Mary” Hunt, accounts differ on who actually brought in the fruit.

Every virus is classified into 7 groups based on genetic differences

Viruses infecting humans have been named based on symptoms ("chickenpox") or the location or animal in which they were first discovered ("Bolivian Haemorrhagic Fever" and "Monkeypox"). For clarity among scientists and to reduce stigma, virologists classify the 15,000 known viruses (270 of which infect humans) by their basic genetic material.

The first computer virus was created by a USC doctoral candidate in 1983

A year after creating malware in a controlled experiment that multiplied until it took over all of a computer's memory, Fred Cohen went public with his research and its risks. He called the self-replicating software a "computer virus," a term Cohen's advisor, Leonard Adleman, coined to describe its infectious behavior. (Some readers may experience a paywall.)

Receptors on the cell surface are key to whether a virus is successful

Viral receptors are key regulators of host range, tissue tropism, and viral pathogenesis—basically, the door locks on cells allowing viruses to invade, if they have the right key. How this process works at the microscopic level determines whether a virus is able to trigger a widespread illness in the host.

Fruit fly experiments helped identify genes responsible for major body development

The insects' fast life cycle and affordability have allowed geneticists to quickly identify which genes are responsible for limbs, eyes, and other body structures by inducing mutations. The same genes may be responsible for different parts of a species' body, such as limb-building genes being responsible for wing pigmentation in butterflies.

Robert Koch won the Nobel for his tuberculosis work, but he also pioneered cholera research

Koch was one of the first scientists to isolate the bacterium that causes cholera while investigating an outbreak in Egypt in 1883. He went on to advise about rules to control cholera outbreaks, which formed the basis of the disease control approaches and water hygiene techniques still used today.

The discovery of nuclear fission was facilitated by the discovery of the neutron

The discovery of the neutron provided scientists with a particle that could penetrate the nucleus and advance atomic physics. Otto Hahn was the sole Nobel recipient for the discovery of fission, despite collaborating with Lise Meitner and Fritz Strassmann.

View an historical mural depicting the NSF's impact across seven decades

From 1950 to 2020, the National Science Foundation supported discovery-based, exploratory research that led to numerous breakthroughs, including the development of supercomputing centers, 3D printing technologies, biometric identification systems, an understanding of vector-borne illnesses, a DNA amplification technique, mobile meteorology units, and scientific education and literacy programming.

Marie Curie pioneered radioactivity research, for which she won two Nobel Prizes

Marie Curie and her husband isolated polonium and radium despite poor lab conditions and financial hardship. President Harding, on behalf of the women of America, presented her with one gram of radium in 1921 in recognition of her service to science.

Penicillin’s pioneers were awarded the Nobel Prize in 1945

Alexander Fleming, Howard Florey, and Ernst Chain received the 1945 Nobel Prize in Physiology or Medicine for discovering and developing penicillin.

How MIT researchers have used genetic mutations to improve photosynthesis efficiency

Recognizing that RuBisCO—a protein that binds carbon dioxide to other compounds to produce the building blocks of organic molecules—often mistakenly binds oxygen, scientists performed directed evolution experiments to modify the geometry of a bacterial version of the protein to cause it to preferentially interact with carbon dioxide over oxygen.

The 2008 Nobel Prize in chemistry was awarded for discovering and developing uses for green fluorescent protein—a biomolecule found in Aequorea victoria, a jellyfish native to the Pacific Northwest.

Before vaccines, there was 'variolation': what was it?

Before the technology behind vaccinations was discovered, some keen observers of medicine around the globe noticed how previous infections could impact future ones. Learn about the techniques early physicians used before they had vaccines.

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.

As of 2026, the Pontifical Academy of Sciences, which advises the pope on scientific matters, has included 90 Nobel laureates among its members.

The pharmaceutical industry evolved, in part, from the discovery of synthetic dyes

In 1856, a chemist accidentally discovered mauveine, the world's first synthetic dye, while trying to make quinine to treat malaria. The synthetic dyes that followed helped reveal germs under microscopes, paving the way for modern imaging techniques and breakthrough treatments, such as antibiotics.

A French Army surgeon discovered that malaria is a parasitic disease in 1880—but scientists were initially skeptical.

The gut microbiome's community of viruses is collectively known as the virome, but most of its viruses remain unidentified.