Marie Curie
Marie Curie was a physicist and chemist and a pioneer in the study of radiation. She and her husband, Pierre, discovered the elements polonium and radium. Together, they were awarded the Nobel Prize for Physics in 1903, and she received another one, for Chemistry, in 1911. Her work with radioactive materials doomed her, however. She died of a blood disease in 1934.
Early life
Maria Salomea Sklodowski was born in Warsaw, Poland, on Nov. 7, 1867. She was the youngest of five children, three older sisters and a brother. Both of her parents were educators and insisted that their girls be educated as well as their son. Maria graduated from high school first in her class at the age of 15.
Maria and her older sister, Bronia, both wished to attend college but the University of Warsaw did not accept women. They were both interested in scientific research; but to get the education they desired they would have to leave the country. At the age of 17, Maria became a governess to help pay for Bronia to attend medical school in Paris. Maria continued to study on her own, looking forward to joining her sister and getting her own degree.
When Maria registered at the Sorbonne, in Paris, she signed her name as Marie to seem more French. She quickly realized her high school education and self-study had not prepared her for the Sorbonne. She had planned to live with Bronia, but took a drafty garret apartment closer to the school so she would have more time to study. To afford the rent, she often subsisted only on bread and tea. Her health suffered, but the hard work paid off. When it was time for the final examinations, she was first in her class. She earned her master’s degree in physics in July 1893. Women’s education advocates gave her a scholarship to stay and take a second degree in mathematics, awarded in 1894.
Meeting Pierre Curie
One of Marie’s professors arranged a research grant for her to study the magnetic properties and chemical composition of steel. In arranging for lab space, she was introduced to a young man named Pierre Curie. Pierre was a brilliant researcher himself and had invented several instruments for measuring magnetic fields and electricity. He arranged a tiny space for her at the Municipal School of Industrial Physics and Chemistry where he worked. The two were married in the summer of 1895.
Marie had been intrigued by the reports of Wilhelm Roentgen’s discovery of X-rays and by Henri Becquerel’s report of similar rays emitted from uranium ores. She decided to use Pierre’s instruments to measure the faint electrical currents she detected in air that had been bombarded with uranium rays. Her studies showed that the effects of the rays were constant even when the uranium ore was treated in different ways. She confirmed Becquerel’s observation that greater amounts of uranium in an ore resulted in more intense rays. Then she stated a revolutionary hypothesis; Marie believed that the emission of these rays was an atomic property of uranium. If true, this would mean that the accepted view of the atom as the smallest possible fragment of matter was false.
Radioactive
Marie next decided to test all of the known many chemical ores to see if any others would emit Becquerel rays. In 1898, she coined the term radioactive to describe materials that had this effect. Pierre was so interested in her research that he put his own work aside to help her. Together, they found that two ores, chalcolite and pitchblende, were much more radioactive than pure uranium. Marie suspected that these ores might contain as yet undiscovered radioactive elements.
Several tons of pitchblende were donated by the Austrian government, but the space Marie was using for a lab was too small. The Curies moved their research to an old shed outside of the school. Processing the ore was backbreaking work. New protocols for separating the pitchblende into its chemical components had to be devised. Marie often worked late into the night stirring huge cauldrons with an iron rod nearly as tall as her.
Little by little, various components of the ore were tested. The Curies found that two of the chemical components, one containing mostly bismuth and another containing mostly barium, were strongly radioactive. In July 1898, the Curies published their conclusion: the bismuth compound contained a previously undiscovered radioactive element that they named polonium, after Marie’s native country, Poland. By the end of that year they had isolated a second radioactive element they called radium, from radius, the Latin word for rays. In 1902, they announced success in extracting purified radium.
In June 1903, Marie was the first woman in Europe to earn a doctorate in physics. In November of that year the Curies, together with Henri Becquerel, were named winners of the Nobel Prize in Physics for their contributions to the understanding of atomic structure. The nominating committee objected to including a woman as a Nobel Laureate, but Pierre insisted that the original research was Marie’s. In 1911, after Pierre’s death, Marie was awarded a second Nobel Prize in Chemistry for her discovery of the elements polonium and radium.
Later years
Marie continued to do research in radioactivity. When World War I broke out in 1914, she suspended her studies and organized a fleet of portable X-ray machines for doctors on the front.
After the war, she worked hard to raise money for her Radium Institute, including a trip to the United States. But by 1920, she was suffering from medical problems, likely due to her exposure to radioactive materials. On July 4, 1934, she died of a plastic anemia, a blood disease that is often caused by too much exposure to radiation.
Maries was buried next to Pierre, but in 1995, their remains were moved and interred in the Pantheon in Paris alongside France’s greatest citizens.
The Curies received another honor in 1944 with the discovery of the 96th element on the Periodic Table of the Elements, which was named curium.
