This week in science history: Marie Curie dies

In its obituary for Marie Curie, who died on July 4, 1934, The New York Times wrote: “Few persons contributed more to the general welfare of mankind and to the advancement of science than the modest, self-effacing woman whom the world knew as Madam Curie. Her epoch-making discoveries of polonium and radium, the subsequent honours that were bestowed upon her – she was the only person to receive two Nobel prizes – and the fortunes that could have been hers had she wanted them, did not change her mode of life.

“She remained a worker in the cause of science … And thus she not only conquered great secrets of science but the hearts of the people the world over.”

Born Maria Sklodowska in Warsaw, Poland, on November 7, 1867, Marie Curie became the first woman to win a Nobel prize and, as The Times noted, at the time she was the only person to win the award twice. 

In 1891 she went to Paris and studied at the Sorbonne, where she was recognised in physics and mathematics. She met Pierre Curie, professor in the School of Physics, in 1894 and they were married the following year. She succeeded her husband as head of the physics laboratory at the Sorbonne, gained her Doctor of Science degree in 1903, and following Pierre’s death in 1906 took his place as professor of general physics in the Faculty of Sciences. It was the first time a woman had held the position.

The Curies built upon the work of French physicist Henri Becquerel, who in 1896 had been investigating X-rays, which had been discovered the previous year.

According to Nobelprize.org, “By accident, [Becquerel] discovered that uranium salts spontaneously emit a penetrating radiation that can be registered on a photographic plate. Further studies made it clear that this radiation was something new and not X-ray radiation.”

The Curies took Becquerel’s work a few steps further. Marie was studying uranium rays and found they were not dependent on the uranium’s form, but on its atomic structure. Her theory created a new field of study, atomic physics. She coined the phrase “radioactivity”.

Marie and Pierre worked with the mineral pitchblende, a form of the crystalline uranium oxide mineral uraninite, which is about 50 to 80% uranium. Through this research, they discovered the radioactive elements polonium and radium. In 1902 the Curies announced that they had produced a decigram of pure radium, demonstrating its existence as a unique chemical element.

In 1903, Marie and her husband won the Nobel prize in physics for their work on radioactivity. In 1911, Marie won her second Nobel, this time in chemistry.

By the late 1920s her health was beginning to deteriorate. She died from leukaemia, caused by exposure to high-energy radiation from her research. The Curies’ eldest daughter Irene was also a scientist, and also won a Nobel prize for chemistry.