🇵🇱🇫🇷Marie
Curie

The university in Warsaw would not admit women. This was the late nineteenth century, and the Russian Empire administered Poland with a firm hand that included, among its provisions, the suppression of Polish language instruction and the exclusion of women from higher education. Maria Sklodowska — who would not become Marie Curie for some years yet — was seventeen, possessed of an extraordinary mind, and faced with a wall. She helped build a door. Together with her sister Bronya, she entered into a pact: Maria would work as a governess, sending her earnings to Paris to fund Bronya's medical degree, and then Bronya would return the support so Maria could follow. In the meantime, Maria attended the clandestine "Flying University," a network of secret classes that moved from apartment to apartment to evade the Russian authorities. She was learning physics while hiding from the police. This is where her story begins — not in a laboratory, but in a conspiracy of determined women.

She arrived in Paris in 1891, at age twenty-four, enrolled at the Sorbonne, and lived in an unheated attic room so cold that the water in her washbasin froze overnight in winter. She ate so little that she sometimes fainted from hunger. She graduated first in her physics degree in 1893 and second in her mathematics degree the following year. In 1894 she met Pierre Curie, an already-respected physicist eight years her senior who was so struck by her work that he offered to share his laboratory. They married in 1895. The collaboration that followed was one of the most consequential in the history of science.

The work that would earn them immortality began with a mystery left by others. Henri Becquerel had discovered in 1896 that uranium emitted rays that could expose photographic plates — a phenomenon nobody understood. Marie chose it as the subject of her doctoral research, coining the term "radioactivity" to describe the property. Working in a leaky wooden shed with inadequate equipment, she and Pierre systematically tested every known element. She discovered that thorium was also radioactive. Then, analyzing pitchblende — a uranium ore — she found that it was far more radioactive than pure uranium alone, which could only mean one thing: there was something else in it, something unknown and intensely active. In 1898, they announced two new elements: polonium, named for her occupied homeland, and radium.

To prove that radium was genuinely a new element required isolating it in pure metallic form — a project that took four years of brutal physical labor, processing literally tons of pitchblende residue in that same leaking shed. In 1902, they had one-tenth of a gram of radium chloride. In 1903, Marie Curie became the first woman to receive a doctorate in physics in France. That same year, she and Pierre shared the Nobel Prize in Physics with Becquerel. The Swedish Academy initially proposed omitting her name from the award; Pierre refused to accept a prize that excluded his wife and co-discoverer. The Academy reconsidered. She was the first woman to win a Nobel Prize.

Pierre was killed in 1906 when he slipped and fell under the wheels of a horse-drawn wagon on a Paris street. Marie was thirty-eight and a widow with two daughters. The Sorbonne offered her Pierre's professorship — she became the first woman to hold a professorship at that institution — and she continued the research. In 1911, she won a second Nobel Prize, this time in Chemistry, for her isolation of pure radium and her study of its properties. She remains the only person in history to have won Nobel Prizes in two different scientific disciplines. The French Academy of Sciences refused to elect her a member, a decision they have since had occasion to regret.

During World War I, Curie developed mobile X-ray units — nicknamed "petites Curies" — that could be driven to the front lines to assist surgeons. She trained over a hundred women as radiological technicians. She estimated that over a million wounded soldiers were examined using her units. She did not patent the radium isolation process, believing scientific knowledge should be freely shared. She did not know, and neither did anyone in the early twentieth century, that the radioactive materials she handled daily with bare hands were destroying her blood. Marie Curie died on July 4, 1934, of aplastic anemia — almost certainly caused by decades of radiation exposure. Her notebooks from the 1890s are still too radioactive to handle safely. They are stored in lead-lined boxes in the Bibliotheque nationale de France. Researchers who wish to consult them must sign a liability waiver.