Six Brilliant Facts About Irène Joliot-Curie

While often eclipsed by the achievements of her famous parents, Irène Joliot-Curie—the firstborn of Marie and Pierre Curie, born in Paris on September 12, 1897—was an exceptional scientist in her own right.

1. SHE WAS DESTINED FOR GREATNESS.

Irène's arrival in Paris in 1897 marked the beginning of a scientific legacy that would change the world. A determined Marie returned to the lab with her devoted husband shortly after Irène’s birth. In the following decade, the Curies uncovered radium and polonium, established the foundation of radioactivity, had a second daughter, Eve, and won a Nobel Prize in Physics. The Curies had high expectations for their daughters' education and careers, and Irène was no exception—by 1925, she held a doctorate in chemistry and was working in her mother’s lab.

2. HER PARENTS' MARRIAGE SET THE STANDARD FOR HER OWN.

Much like her mother, Irène fell in love in the lab—not only with her scientific pursuits but with another researcher. Frédéric Joliot became part of the Curie team as an assistant. Irène and Frédéric quickly discovered a shared passion for sports, the arts, and human rights. Their collaboration in research led to a marriage, and they combined their names to sign their work as Irène and Frédéric Joliot-Curie.

3. TOGETHER, SHE AND HER HUSBAND WERE A FORCE TO BE RECKONED WITH.

Their relentless curiosity propelled them into uncharted scientific territory. A decade of rigorous experimentation brought breakthroughs across multiple fields. They discovered how the thyroid gland absorbs radioiodine and how radioactive phosphates are processed by the body. They also figured out how to extract radioactive isotopes from non-radioactive materials—a key discovery that paved the way for both nuclear energy and atomic weapons, earning them the Nobel Prize in Chemistry in 1935.

4. THEY STOOD UP FOR JUSTICE AND PEACE.

The humanistic ideals that initially brought Irène and Frédéric together only deepened with time. Both were proud members of the Socialist Party and the Comité de Vigilance des Intellectuels Antifascistes (Vigilance Committee of Anti-Fascist Intellectuals). They worked tirelessly to keep atomic research away from the Nazis, safeguarding and hiding their findings as Germany occupied France. Irène also held the position of undersecretary of state for scientific research in the Popular Front government.

5. SHE WASN'T SATISFIED WITH THE STATUS QUO.

Irène eventually reduced her time in the lab to raise her children, Hélène and Pierre. However, she never lost her momentum or her commitment to the fight for equality and freedom. A staunch advocate for women’s rights, she joined the Comité National de l'Union des Femmes Françaises and the World Peace Council.

6. SHE DEDICATED HERSELF TO THE POINT OF EXHAUSTION.

Irène's remarkable life reflected her mother’s, and sadly, so did her death. Despite witnessing the toll of radiation poisoning and cancer on Marie, Irène remained unwavering in her dedication to her work. In 1956, as she succumbed to leukemia, she entered the Curie Hospital, following in her mother's radiant footsteps into eternity.