A century ago, Marie Curie, now widowed, received the Nobel chemistry prize for the discovery of radium and polonium, eight years after she and husband Pierre had shared the 1903 Nobel physics prize with Henri Becquerel for their research into radioactivity.
The atomic age is a mixed blessing, but the story of the Curies’ discovery of polonium and radium is a wonderful example of love and intelligence working together to expand human knowledge.
Marie Sklodowska and Pierre Curie
It was good to be a scientist in France in the 1890s, and 24-year-old Marie Sklodowska, from Warsaw, was there, studying at the College de France. In 1893, two years after coming to Paris, she had taken her degree in physics and the next year came in second in a mathematics degree. Now, however, she had a problem.
An industrial society had ordered a study from Marie on the magnetic properties of various steels, but the lab she was working in had no room for this project. A friend from Poland referred her to “a scientist of great merit who works in the School of Physics and Chemistry,” one Pierre Curie.
Things happened quickly once Marie and Pierre met. He helped her get the laboratory space she needed, and he was also quite taken with her. These two brilliant people fell in love and formed a partnership that changed the world.
Marie encouraged Pierre to turn his work on magnetism into a doctoral thesis, and a few months before their marriage in 1895, he was awarded his doctorate of science for a presentation of the relationship between magnetism and temperature that is known today as Curie’s Law. In 1896, Marie Curie passed her teacher’s diploma, coming in first. In 1897, she completed her studies on magnetic properties of various steels and started looking into topics for her own doctoral thesis.
Radium and polonium
She found something interesting that fellow scientist Henri Becquerel had published the previous year. While studying X-rays, Becquerel had accidentally discovered that uranium salts gave off what Marie called “rays of a peculiar character.” She chose to make the investigation of these rays the topic of her thesis.
Using equipment designed by Pierre, Marie studied uranium and thorium and soon realized that pitchblende ore was much more active than it should be from its uranium content. There had to be another radioactive element in there, one that had not yet been recognized.
Pierre set aside his own work and joined Marie in the hunt. Their chemical analyses eventually showed a substance that was about 300 times more active than uranium, which they called “polonium,” in honor of Marie’s native land, and then another new element that they christened “radium.”
Marie collected a tiny amount of almost pure radium chloride, proving the existence of this new element. Her findings, presented on June 25, 1903, were described by her committee as the greatest scientific contribution ever made in a doctoral thesis.
An inspirational quote has long been attributed to Marie Curie : “Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.”
These words can help us live in the nuclear age that the Curies and others bequeathed to us a century ago. May we live, not in fear, but always with a will to understand more how to maximize the good this power brings us and how to reduce its evils.
“Marie and Pierre Curie and the Discovery of Polonium and Radium”. Nobelprize.org. September 23, 2011 http://www.nobelprize.org/nobel_prizes/physics/articles/curie/
Susan Quinn. “Marie Curie: a life,” page 134 . Da Capo Press: 1995. Books.google.com. September 23, 2011.