Marie Sklodowska Curie

views updated May 29 2018

Marie Sklodowska Curie

The Polish-born French physicist Marie Sklodowska Curie (1867-1934) pioneered radioactive research by her part in the discovery of radium and polonium and in the determination of their chemical properties.

Marie Curie was born in Warsaw on Nov. 7, 1867, the youngest of the five children of Wladislaw and Bronislava Boguska Sklodowska. Marie was a brilliant student, gaining a gold medal upon completing her secondary education in 1883. As girls could not attend universities in Russian-dominated Poland, Marie at her father's suggestion spent a year in the country with friends. On returning to her father's house in Warsaw the next summer, she had to begin to earn her living through private tutoring, and she also became associated with the "Floating University," a group of young men and women who tried to quench their thirst for knowledge in semiclandestine sessions. In early 1886 she accepted a job as governess with a family living in Szczuki, but the intellectual loneliness she experienced there only stiffened her determination to achieve somehow her dream to become a university student. One of her sisters, Bronya, was already in Paris, successfully passing the examinations in medicine. In March 1890 she offered hospitality to Marie whose acceptance was a foregone conclusion, but it was not until September 1891 that she could leave for Paris.

When classes began at the Sorbonne in Paris in early November 1891, she enrolled as a student of physics. By 1894 she was desperately looking for a laboratory where she could work on her research project, the measurement of the magnetic properties of various steel alloys, and it was suggested that she see Pierre Curie at the School of Physics and Chemistry of the University of Paris. Their first meeting was movingly recorded in the future Madame Curie's recollections: "He seemed very young to me although he was then age thirty-five. I was struck by the expression of his clear gaze and by a slight appearance of carelessness in his lofty stature. His rather slow, reflective words, his simplicity, and his smile, at once grave and young, inspired confidence. A conversation began between us and became friendly; its object was some questions of science upon which I was happy to ask his opinion."

Although she was insistent from the very start that she would go back to Poland in half a year to assist her subjugated country in whatever way she could, Pierre Curie was most intent to see her more and more often. The result was that she returned to Paris in October 1894 after spending the summer months in Poland. The next summer witnessed their wedding and the beginning of a most extraordinary partnership in scientific work. By mid-1897 Curie could list as her scientific achievements two university degrees, a fellowship, and a monograph on the magnetization of tempered steel. Their first daughter, lrène, had just been born, and it was in that euphoric atmosphere that the Curies' attention turned to the mysterious radiation from uranium recently discovered by Antoine Henri Becquerel. It was Curie's hunch that the radiation was an atomic property and therefore had to be present in some other elements as well. Her search soon established the fact of a similar radiation from thorium, and the historic word "radioactivity" was coined by her.

While searching for other sources of radioactivity, the Curies had before long to turn their attention to pitchblende, a mineral well known for its uranium content. To their immense surprise the radioactivity of pitchblende far exceeded the combined radioactivity of the uranium and thorium contained in it. From their laboratory two papers reached the Academy of Sciences within 6 months. The first, read at the meeting of July 18, 1898, announced the discovery of a new radioactive element, which the Curies named polonium after Curie's native country. The other paper, announcing the discovery of radium, was read at the December 26 meeting.

To substantiate the existence of the new elements and to establish their properties, the Curies had to have sufficiently large quantities. Fortunately, the Austrian government was willing to give the Curies a ton of pitchblende, but to process it a laboratory was needed. After long search, the Curies had to settle for a shed occupying part of a courtyard in the School of Physics and Chemistry. From 1898 to 1902 the Curies processed several tons of pitchblende, but it was not only the extremely precious centigrams of radium that rewarded their superhuman labors. The Curies also published, jointly or separately, during those years a total of 32 scientific papers. Among them was the one which announced that diseased, tumor-forming cells were destroyed faster than healthy cells when exposed to radium.

From abroad came the full measure of recognition which the French Academy of Sciences refused to give in 1902, when Pierre Curie presented himself as candidate for membership. In November 1903 the Royal Society in London gave the Curies one of its highest awards, the Davy Medal; and a month later followed the announcement from Stockholm that three French scientists, A. H. Becquerel and the Curies, were the joint recipients of the Nobel Prize in physics for 1903. Finally even the academics in Paris began to stir and a chair in physics was created at the University of Paris, and a few months later Curie was appointed director of research associated with the new chair. In December 1904 their second daughter Ève, was born; while the next year brought the election of Pierre Curie to the Academy of Sciences and their travel to Stockholm, where he delivered on June 6 the Nobel lecture, which was in fact their joint address. Its concluding paragraph evoked in prophetic words the double-edged impact on mankind of every major scientific advance. Still Pierre Curie asserted his conviction that "mankind will derive more good than harm from the new discoveries."

The illustrious husband-and-wife team, now installed in more appropriate academic positions, had, however, their happy days numbered. The first academic year of Pierre Curie in his new professorship was not over when, on the rainy mid-afternoon of April 19, 1906, he was run down by a heavy carriage and killed instantly. Two weeks later the widow was asked to take over her late husband's post. Honors began to pour in from scientific societies all over the world on a woman left alone with two small children and with the gigantic task of leadership in radioactivity. In 1908 she began to give as titular professor at the Sorbonne the first, and then the only, course on radioactivity in the world. In the same year she edited the collected works of her late husband, and in 1910 she published her massive Traitéde radioactivité. The next year the Academy of Sciences showed once more its true colors by denying with a one-vote majority the membership to the person who 11 months later became the first to receive twice the Nobel Prize, this time in chemistry.

In addition to the Nobel Prize the two finest honors that came to Curie in 1911 were her election as permanent member of the Solvay Conferences in physics and the erection in Warsaw of the Institute of Radioactivity, whose directorship was offered to her by a most distinguished group of Polish intellectuals. The first of these honors reflected on her stature as a scientist. The second honor was more of an emotional satisfaction and represented some temptation for her to turn her back on the unappreciative scientific establishment of her adopted country. But she decided to stay in France, though she did her best to assist the new institute in Warsaw in every possible way. A most important factor in Curie's decision to stay was the future of the laboratory which Dr. P. P.E. Roux, the director of the Pasteur Institute, proposed to build for her. The plan finally jolted the Sorbonne to join hands with the Pasteur Institute in establishing the famous Radium Institute. Its dedication took place in July 1914, a year after the institute in Warsaw had been dedicated in her presence.

Curie devoted much of her time during the 4 years of World War I to equipping automobiles in her own laboratory with x-ray (Roentgen) apparatus to assist the sick. It was these cars that became known in the war zone as "little Curies." By the end of the war Curie was past her fiftieth year with much of her physical energy already spent, together with her savings, which she had patriotically invested in war bonds. But her dedication seemed to be inexhaustible. The year 1919 witnessed her installation at the Radium Institute, and 2 years later her book La Radiologie et la guerre was published. In it she gave a most informative account of the scientific and human experiences gained for radiology during the war. With the end of the war also came the appointment of her daughter Irène, a physicist, as an assistant in her mother's laboratory.

Shortly afterward, a momentous visit took place in the Radium Institute. The visitor was Mrs. William B. Meloney, editor of a leading magazine in New York and representative of those countless women who for years had found in Curie their ideal and inspiration. A year later Meloney returned to tell her that a nationwide subscription in America had produced the sum of $100,000 needed to purchase a gram of radium for her institute. She was also asked to visit the United States with her daughters and collect in person the precious gift. Her trip was a triumph in the finest sense of the word. In the White House, President Warren G. Harding presented her with the golden key to the little metal box containing the radium.

On questions other than scientific, Curie rarely uttered public comment of any length. One of the exceptions was her statement at a conference in 1933 on "The Future of Culture." There she rallied to the defense of science, which several panelists held responsible for the dehumanization of modern life. "I am among those," she emphasized, "who think that science has great beauty. A scientist in his laboratory is not only a technician; he is also a child placed before natural phenomena which impress him like a fairy tale. We should not allow it to be believed that all scientific progress can be reduced to mechanism, machines, gearings, even though such machinery also has its own beauty."

The most heartwarming experience of the last phase of Curie's life was probably the marriage of Irène in 1926 to Frédéric Joliot (later Joliot-Curie), the most gifted assistant at the Radium Institute. Before long it was evident to her that their union would be a close replica of her own marvelously creative partnership with Pierre Curie.

She worked almost to the very end and succeeded in completing the manuscript of her last book, Radioactivité. In the last years her great support was her younger daughter, Ève. She was also her mother's faithful companion when, on July 4, 1934, death claimed the one of whom Albert Einstein aptly said, "Marie Curie is, of all celebrated beings, the only one whom fame has not corrupted."

Curie, Marie Sklodowska

views updated May 23 2018

Curie, Marie Sklodowska

POLISH/FRENCH PHYSICIST
1867–1934

Physicist-chemist Marie Sklodowska Curie, sometimes referred to as the "mother of atomic physics," is perhaps the best-known woman scientist of all time—a legend of twentieth-century science. Cowinner of the Nobel Prize in physics in 1903, she was the first person to be awarded a second Nobel Prize, this time in chemistry, in 1911.

Marya Sklodowska was born in Warsaw, Poland, on November 7, 1867. Educated in government schools, she worked for several years in Poland as a governess before going to Paris in 1891 for further study. By dint of considerable effort she completed the physics course at the Sorbonne in 1893, and the course in mathematics the following year. She married physicist Pierre Curie in 1895.

Although her first research focused on the magnetic properties of steel, for her doctoral work she moved to the new field of "radioactivity," as it came to be called. Her studies, a continuation of the work of her teacher, physicist Henri Becquerel, developed directly from Becquerel's 1895 observation that uranium minerals emit rays that pass through opaque materials and fog a photographic plate (as well as discharge an electroscope by making the surrounding air conductive). Marie Curie, with the collaboration of her husband, undertook a systematic investigation of the Becquerel radiation to try to discover its source. Their starting material was the residue left after the extraction of uranium from pitchblende, a uranium ore. The fact that this residue was more radioactive than purified uranium oxide suggested it as a likely source for some unknown material more radioactive than uranium.

Her work at this time was done in minimal facilities that had been secured for her by Pierre Curie at the Paris École Municipale de Physique et de Chimie Industrielle, the industrial college at which he was teaching. With the collaboration, initially, of Gustav Bémont, head of the chemistry section of the École Municipale, she took on the laborious task of isolating the postulated unknown material by chemical methods (group separation and fractional crystallization ). Pierre Curie established the electrical properties of the rays emitted by the fractions. In June 1898, following their isolation of a fraction 400 times more radioactive than uranium, the Curies reported the presence in the fraction of what was probably a new element. That element, named polonium by Marie Curie, was the first element discovered via its property of radioactivity. Six months later, working with a different fraction, the Curies discovered a second new element. It was given the name radium. In spite of its still impure state, it had an activity a million times that of uranium.

In 1902 Marie Curie succeeded in isolating one-tenth of a gram (0.0035 ounces) of pure radium chloride from eight tons of pitchblende residue, a task that required an enormous amount of physical labor. The atomic weight of radium she determined to be 225. These results aroused immediate interest. She received her doctoral degree in 1903, her radioactivity investigations forming the major part of her thesis. It was undoubtedly one of the most remarkable doctoral theses ever written. Her Nobel Prize in physics, shared that same year with Henri Becquerel and Pierre Curie, received unprecedented press coverage. Pierre Curie was appointed to a professorship in physics at the Sorbonne in 1904. He died suddenly in 1906.

From 1900 until 1904 Marie Curie taught physics at a college for women teachers in the Paris suburb of Sèvres. In 1906, after her husband's death, she succeeded to his professorship in physics, becoming the first woman to hold a teaching post at the Sorbonne. Her scientific research continued, and the tremendous world interest in the new field of radioactivity, coupled with her own international prestige, attracted many students and research workers to her laboratory in the period leading up to World War I. To a notable extent, however, she stepped aside from the increasingly competitive field of atomic physics (which she had in part created) after 1906, and left to others, for example, Ernest Rutherford and his colleagues, the further theoretical development of modern atomic theory . Her own work after 1906 tended more toward radiochemistry, and consisted, primarily, of investigations of the radioactive elements (including the substances that came to be called isotopes ) and their disintegration processes and products. A number of her students and coworkers made notable contributions to both radiochemistry and physics that included: the development of instrumentation for the detection of subatomic particles; characterizations of the range (distance traveled from source) and energy of α -particles ; descriptions of the effects of α -particles on chemical processes; investigation of β -rays; and the disintegration products in the thorium series. Marie Curie's Nobel Prize in chemistry (1911) was awarded for her discoveries of radium and polonium, and the isolation of radium and the study of its properties.

The applications of radiation as a diagnostic tool in medicine were quickly recognized. With the coming of World War I, Curie became director of the Red Cross Radiological Service and worked with her daughter Irène to provide radiology stations for the French army. In 1918 she began work at the new Paris Institute of Radium. She continued to lecture at the Sorbonne until 1934, but gradually turned over the leadership of her laboratory at the Institute of Radium to her daughter and her son-in-law, Frédéric Joliot. By the 1920s she was in poor health. The high doses of radiation to which she had been exposed over the years had taken their toll. Despite failing health, to raise funds for the support of the institute, she made several speaking tours in Europe and the United States. Although never accepted into the Paris Academy of Sciences, she was the first woman elected to the French Academy of Medicine. She died on July 4, 1934, of leukemia, misdiagnosed as tuberculosis, in a nursing home in the Département of Haute-Savoie region of France.

PIERRE CURIE

Electromagnetic rays emitted by radioactive materials are classifiable into three distinct groups: alpha (α ), beta (β ), and gamma (γ ). Seminal studies by Pierre Curie, the Curie team's major investigator of these rays, include his study of α -rays, his demonstration that β -rays are negatively charged, and his observation (with Marie Curie) that radium causes induced radioactivity.

see also Becquerel, Antoine-Henri; Polonium; Radioactivity; Radium; Rutherford, Ernest; Thorium; Uranium.

Mary R. S. Creese

Bibliography

Bensaude-Vincent, Bernadette, and Stengers, Isabelle (1993). Histoire de la Chimie. Paris: Éditions la Decouverte.

Curie, Eve (1938; reprint 1986). Madame Curie, tr. V. Sheean. New York: Da Capo.

Davis, J. L. (1995). "The Research School of Marie Curie in the Paris Faculty, 1907–14." Annals of Science 52:321–355.

Partington, J. R. (1964). A History of Chemistry, Vol. 4. London: Macmillan.

Quinn, Susan (1995). Marie Curie: A Life. New York: Simon & Schuster.

Reid, Robert (1974). Marie Curie. New York: Saturday Review Press.

Svoronos, Soraya (1993). "Marie Sklodowska Curie (1867–1934)." In Women in Chemistry and Physics: A Biobibliographic Sourcebook, ed. Louise Grinstein, Rose K. Rose, and Miriam H. Rafailovich. Westport, CT: Greenwood Press.

Chemistry: Foundations and Applications Creese, Mary R. S.

Marie Sklodowska Curie

views updated May 17 2018

Marie Sklodowska Curie

1867-1934

Polish-born French Chemist

One of the pioneering figures in early nuclear physics and radiochemistry, Marie Curiewas the first woman to win a Nobel Prize, the first person to win two Nobel Prizes (in 1903 and 1911), and remains the only person to win both prizes in the same field, and to be the mother of another Nobel Prize winner—Irène Joilot-Curie (1897-1956). Her extraordinary accomplishments served to break down many social and cultural barriers that had previously prevented women from pursuing careers as research scientists.

Maria Sklodowska was the daughter of Polish intellectuals suffering repression under the Russian occupation of their homeland. Despite such circumstances, her parents provided her with a thorough education. As a young woman, she worked as a governess before leaving for Paris in 1891 to live with relatives and pursue further studies, changing her first name to its French form, Marie. In 1893 she received her diploma in physics with high honors—an extraordinary distinction for a woman at that time—and in 1894 a second diploma in mathematics with honors. In April 1894 she met the promising young physicist Pierre Curie (1859-1906); they married in July 1895 and their daughter Irène was born in 1897.

The course of the Curies's scientific researches was set by the 1895 discovery of "xrays" from uranium by Wilhelm Roentgen (1845-1923). Pierre and Marie undertook the laborious task of purifying several tons of pitchblende (impure uranium ore) to obtain only a few pounds of concentrated radioactive material. Early in 1898 Marie noted that the samples thereby obtained appeared to contain other substances besides uranium. In July this suspicion was confirmed when measurements of rates of radioactive emissions revealed the presence of another element, named "polonium" in honor of Marie's homeland. In November, spectroscopic analysis performed for them by Eugène Demarcay (1852-1903) disclosed the existence of a second element, named "radium," though it was not successfully isolated until 1902.

Meanwhile, in 1900 Marie assumed a position as the first female faculty member at the Ecole Normale Supérieure, an all-women's school in Sèvres. In 1903 she defended her research thesis on analysis of radiation from uranium at the Sorbonne. That same year, Marie and Pierre shared the prestigious Humphrey Davy Medal from England, and then the Nobel Prize with Henri Becquerel (1852-1908) for research on radioactivity. In 1904 a second daughter, Eve, was born, and Marie was finally allowed to join her husband, who was a member of the Faculty of Sciences at the Sorbonne, as his research assistant. This seemingly idyllic picture was shattered when Pierre was struck and killed by a horse-drawn carriage in April 1906.

The faculty of the Sorbonne thereupon offered Marie the professorship held by her late husband. This appointment was officially confirmed in 1909, making her the first female faculty member of one of the world's most prestigious universities. However, Madame Curie's life was not free from controversy; in 1910 she declined the award of the Legion of Honor, as Pierre had done in 1903, and in 1911 she was rejected for membership in the Académie des Sciences after public controversy surrounding her involvement in an extramarital affair. The award of a second Nobel Prize later that year for her discoveries of polonium and radium, along with her belated election to the Académie in 1914 and role as a founding member of the Conseil de l'Institut du Radium, represented, however, a vindication of her scientific work and reputation.

Marie continued her researches into radioactivity together with her daughter and sonin-law, Irène and Frederic Joilot-Curie, up until her death from leukemia, due to many years of unprotected exposure to radiation at a time when its hazards were not yet known.

JAMES A. ALTENA

Science and Its Times: Understanding the Social Significance of Scientific Discovery