Geniuses Who Saw the Invisible · Story 02

Marie Curie: The Scientist Who Brought X-Rays to the Battlefield

When the First World War began, Marie Curie had already won two Nobel Prizes and transformed humanity’s understanding of matter. She could have remained protected inside a laboratory. Instead, she learned to drive, converted automobiles into radiology rooms, and brought X-ray equipment to hospitals near the front.

When the First World War began, Marie Curie had already won two Nobel Prizes and transformed humanity’s understanding of matter. She could have remained protected inside a laboratory. Instead, she learned to drive, converted automobiles into radiology rooms, and brought X-ray equipment to hospitals near the front.

These vehicles, later known as the petites Curies, allowed physicians to locate bullets and fragments of shrapnel before operating. Curie did more than promote the idea: she obtained equipment, studied anatomy, repaired machines, trained technicians, and personally traveled through military zones.

The woman who had discovered invisible elements inside a mineral went on to use another invisible form of radiation to look inside the human body.

A clandestine student in an occupied city

Maria Salomea Skłodowska was born in Warsaw on November 7, 1867, when much of Poland was controlled by the Russian Empire. The authorities attempted to weaken Polish culture and maintained strict control over education. Her family, composed of teachers, valued knowledge deeply but endured financial hardship and personal loss.

Polish universities did not admit women. Maria attended clandestine courses associated with the so-called Flying University, a secret institution whose classes changed location to evade Russian surveillance.

She and her older sister, Bronisława, made an agreement. Maria would work as a governess to finance her sister’s medical education in Paris. Bronisława would later help Maria study there.

For several years, Maria taught the children of affluent families while continuing her own education at night. In 1891, at the age of twenty-four, she finally traveled to Paris. There she began using the French form of her name: Marie.

Hunger, cold, and science in Paris

Marie enrolled in the Faculty of Sciences at the University of Paris. She lived in small rooms, studied late into the night, and sometimes lacked adequate food and heating. In 1893, she finished first in her physics degree and obtained a second degree in mathematics the following year.

While searching for laboratory space to investigate the magnetic properties of different steels, she met Pierre Curie. He was already respected for his work on crystals, magnetism, and piezoelectricity. They married in 1895.

Their relationship was both personal and scientific. Pierre quickly recognized Marie’s intellectual ability and, when she began a promising investigation into a mysterious form of radiation, chose to collaborate with her.

Henri Becquerel had discovered that uranium salts spontaneously released radiation capable of penetrating opaque materials. Curie selected this phenomenon as the subject of her doctoral research.

Rather than relying exclusively on photographic plates, she used a sensitive electrometer developed by Pierre and his brother Jacques. It allowed her to measure the electricity produced when radiation ionized the surrounding air.

Her results indicated that the emission did not depend on the chemical form of uranium. It was a property of the atom itself—a revolutionary conclusion when many scientists still regarded the atom as indivisible.

Marie called the phenomenon radioactivity.

Two elements hidden inside a rock

While examining pitchblende, a mineral containing uranium, Curie discovered that it emitted more radiation than its uranium content could explain. She concluded that it must contain other, unknown elements that were far more active.

In July 1898, Marie and Pierre announced the existence of one of them. They named it polonium after Poland, which did not then exist as an independent state. The name transformed a scientific discovery into a quiet political declaration.

In December, they announced a second element: radium.

Proving its existence required much more than detecting radiation. The Curies worked in rudimentary conditions, processing large quantities of mineral residue inside a poorly ventilated shed. Marie stirred heavy containers and performed repeated chemical separations to concentrate minute quantities of radioactive material.

By 1902, she had obtained enough radium compound to determine its atomic weight. The result confirmed that radium was not an anomaly produced by uranium but a new element.

Marie and Pierre chose not to patent their method for separating radium. They believed scientific knowledge should remain available to other researchers and physicians. The decision encouraged further research, although it also allowed private companies to market radium products without adequate safeguards.

Two Nobel Prizes and a door that remained closed

In 1903, Henri Becquerel, Pierre Curie, and Marie Curie received the Nobel Prize in Physics for their research into radiation phenomena. Marie became the first woman awarded a Nobel Prize.

Her inclusion had not been automatic. The original proposal considered by the committee mentioned only Becquerel and Pierre. Swedish mathematician Gösta Mittag-Leffler informed Pierre, who insisted that Marie’s contribution be recognized (Nobel Prize Outreach, n.d.).

Pierre died in 1906 after being struck by a horse-drawn vehicle on a Paris street. The University of Paris offered Marie the chair he had occupied. She consequently became the first woman to teach as a professor at the Sorbonne.

Five years later, she received the Nobel Prize in Chemistry for the discovery of radium and polonium, the isolation of radium, and the study of its compounds. She became the first person to win two Nobel Prizes and remains the only person to receive them in two different scientific disciplines.

That same year, the French Academy of Sciences rejected her application for membership. A woman with two Nobel Prizes could still be considered unsuitable for one of France’s principal scientific institutions.

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A scientist confronted by war

When Germany invaded France in 1914, military hospitals filled with soldiers wounded by bullets and shrapnel. Surgeons often had to operate without knowing exactly where foreign objects were lodged inside the body.

X-ray machines already existed, but they were large, scarce, and located mostly far from the battlefield. Curie understood that the technology had to be transported to the wounded.

She obtained automobiles, electrical generators, radiology equipment, and support from organizations including the Red Cross. The vehicles could travel between hospitals and produce images revealing fractures and pieces of metal. Approximately twenty mobile units eventually operated during the war, supported by numerous permanent radiology installations (American Institute of Physics, n.d.).

Soldiers came to call the vehicles petites Curies—little Curies.

Marie understood physics but needed practical medical knowledge. She studied anatomy and radiological procedures. She also learned mechanics and driving because early automobiles broke down frequently and specialists were not always available.

Her daughter Irène, who was seventeen when the war began, accompanied her and worked as a radiology technician in military hospitals. Irène and Frédéric Joliot-Curie later received the 1935 Nobel Prize in Chemistry for discovering artificial radioactivity.

The women trained to see beneath the skin

Curie realized that machines were useless without trained operators. She created intensive courses for radiology technicians. The students learned electricity, anatomy, photography, geometry, and the operation of X-ray tubes.

She trained more than one hundred women, many of whom were assigned to military hospitals. At a time when scientific opportunities for women remained severely restricted, Curie created a setting in which they operated advanced technology and assumed clinical responsibilities.

Sources differ on the exact number of soldiers examined through the services she organized. What is historically certain is that radiology allowed more precise diagnoses and reduced the need for exploratory operations. Curie did not “invent” the X-ray—Wilhelm Röntgen discovered it in 1895—but she organized its mobile and systematic use under wartime conditions.

Curie herself had little protection. The consequences of repeated radiation exposure were not yet fully understood. She and the technicians worked near machines without modern shielding or instruments capable of monitoring accumulated doses.

The radiation that illuminated and destroyed

After the war, Curie returned to research and promoted the medical use of radium, especially in treating tumors. She directed the Radium Institute in Paris and supported the establishment of another institute in Warsaw.

Her fame did not always provide the resources her laboratory required. In 1921, American journalist Marie Meloney organized a campaign among women in the United States to purchase one gram of radium for Curie’s research. President Warren G. Harding presented it to her during a ceremony at the White House.

Marie Curie died on July 4, 1934, at the Sancellemoz sanatorium in France. The cause was aplastic anemia, a condition in which the bone marrow stops producing sufficient blood cells. Her cumulative exposure to radiation over decades—both in laboratories and around unshielded X-ray equipment during the war—is considered the most probable cause (Nobel Prize Outreach, n.d.).

She did not die simply because she “touched radium” on one occasion. Her illness was the probable consequence of years of work conducted before modern radiation-safety standards existed.

Science transformed into service

Marie Curie is frequently pictured as a solemn woman standing beside laboratory instruments. That image can make us forget that she was also an organizer capable of transforming a physical discovery into a medical network.

She did more than discover polonium and radium. She changed the conception of the atom, opened paths toward nuclear physics and radiological medicine, directed scientific institutions, and prepared other women to enter spaces reserved almost entirely for men.

During the war, she could have protected her prizes, her laboratory, and her reputation. Instead, she carried science over damaged roads to places where it could save actual human bodies.

The rays she studied were invisible. Their effect on history was not.