Marie Curie

Marie Curie's story is one of extraordinary perseverance and groundbreaking scientific achievement. Born Maria Salomea Skłodowska on November 7, 1867, in Warsaw, Poland (then part of the Russian Empire), she was the youngest of five children of Bronisława, a pianist, singer, and teacher, and Władysław Skłodowski, a mathematics and physics instructor. Her family valued education, but women were not allowed to attend university in Poland. After her mother's death from tuberculosis when Maria was ten, and her sister Zofia's death from typhus, the family faced financial hardship. Maria and her sister Bronisława made a pact: Maria would work to support Bronisława's medical studies in Paris, and then Bronisława would reciprocate. Maria worked as a governess and tutor, and in her spare time, she secretly studied chemistry and physics at the clandestine "Floating University" in Warsaw.

In 1891, Maria finally joined her sister in Paris and enrolled at the Sorbonne (University of Paris). She adopted the French name Marie and dedicated herself intensely to her studies, often surviving on little food and enduring cold, but achieving top honors. She earned a degree in physics in 1893 and mathematics in 1894. While seeking laboratory space, she met Pierre Curie, a brilliant physicist and professor at the School of Industrial Physics and Chemistry. They shared a passion for science and married in July 1895, beginning one of history's most productive scientific partnerships.

At the time, Henri Becquerel had discovered that uranium salts emitted rays that could fog photographic plates. Marie decided to investigate these "uranium rays" for her doctoral thesis. She hypothesized that the emission was an atomic property of the element uranium. Using an electrometer invented by Pierre and his brother Jacques, she measured the ionization produced by uranium compounds. She soon discovered that thorium also emitted such rays. Crucially, she found that the mineral pitchblende was more radioactive than pure uranium, suggesting the presence of other, more radioactive elements.

Pierre joined her in the search, and in 1898, they announced the discovery of two new elements: polonium, named after Marie's native Poland, and radium, derived from the Latin word for ray. To isolate these elements, they had to process tons of pitchblende in a makeshift shed, working under harsh conditions. Marie carried out the chemical separations, while Pierre concentrated on the physical properties. In 1902, they succeeded in isolating a decigram of pure radium chloride, and Marie determined its atomic weight. She presented her doctoral thesis in 1903, becoming the first woman in France to complete a doctorate in science.

That same year, the Curies and Becquerel were jointly awarded the Nobel Prize in Physics for their research on radioactivity. The award brought international fame, but also controversy, as some attempted to downplay Marie's contributions. Nevertheless, she became the first female Nobel laureate. The prize money allowed them to improve their laboratory and hire assistants.

In 1906, Pierre was tragically killed in a street accident, leaving Marie devastated. However, she continued their work and was appointed to Pierre's professorship at the Sorbonne, becoming the university's first female professor. She established a major laboratory and continued to investigate radium's properties. In 1911, she won the Nobel Prize in Chemistry for the discovery of polonium and radium and for the isolation and study of radium. This made her the first person and only woman to win two Nobel Prizes, and the only person to win in two scientific fields.

Despite her accolades, Curie faced xenophobia and sexism. In 1911, her affair with physicist Paul Langevin, a former student of Pierre's who was married, became public. The press vilified her, and some urged her to leave France. Yet, she stood resilient and continued her work.

During World War I, Curie applied her scientific knowledge to practical aid. She developed mobile X-ray units, called "petites Curies," and set up radiological centers, training nurses and doctors. She and Irène personally drove these units to field hospitals, helping to locate shrapnel and fractures in wounded soldiers. After the war, she continued research at the Radium Institute in Paris, which she had founded. She traveled to the United States in 1921 to raise funds for radium research, meeting President Harding and receiving a gift of a gram of radium from American women.

In her later years, Curie suffered from health problems caused by prolonged radiation exposure, including cataracts and aplastic anemia. She died on July 4, 1934, at the Sancellemoz sanatorium in Passy, France. The Curie Institutes in Paris and Warsaw, which she founded, became leading cancer research and treatment centers. Her daughter Irène Joliot-Curie continued the family legacy, winning the Nobel Prize in Chemistry in 1935 with her husband Frédéric Joliot for their discovery of artificial radioactivity.

Marie Curie's impact on science and society is immeasurable. She fundamentally changed our understanding of matter and energy, coined the term radioactivity, and laid the groundwork for nuclear physics and cancer therapy. Her perseverance in the face of discrimination paved the way for countless women in science. Her notebooks, still radioactive, are preserved in lead-lined boxes and serve as a poignant testament to her dedication and the personal costs of her discoveries.