Margaret Melhase Fuchs (August 13, 1919August 8, 2006) was an American chemist and a co-discoverer, with

Glenn T. Seaborg Glenn Theodore Seaborg (; April 19, 1912February 25, 1999) was an American chemist whose involvement in the synthesis, discovery and investigation of ten transuranium elements earned him a share of the 1951 Nobel Prize in Chemistry. His work i ...

, of the isotope

caesium-137 Caesium-137 (), cesium-137 (US), or radiocaesium, is a radioactive isotope of caesium that is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nucl ...

Education and research career

In 1940, Melhase was an undergraduate in the college of chemistry at the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

. She was president of the

Student Affiliates of the American Chemical Society The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all d ...

and was considering doctoral studies and a career in chemistry. Honors students typically took on research projects at the time, and she sought advice from her close friend, nuclear chemist

Gerhart Friedlander Gerhart Friedlander (July 28, 1916 in Friedländer – September 6, 2009) was an American nuclear chemist who worked on the Manhattan Project. Friedlander was born in Munich, and fled Nazi Germany for the United States in 1936. After emigrating, h ...

; Friedlander was then a graduate student under the supervision of

, and he suggested she approach him for a project. She spoke to Seaborg in his lab, and he proposed they work together to search for a

Group 1 element The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K),The symbols Na and K for sodium and potassium are derived from their Latin names, ''natrium'' and ''kalium''; these are still the origins of the names ...

among the fission products of

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

. Her laboratory was above those of Nobel Prize winners

Willard Libby Willard Frank Libby (December 17, 1908 – September 8, 1980) was an American physical chemist noted for his role in the 1949 development of radiocarbon dating, a process which revolutionized archaeology and palaeontology. For his contributions ...

and

Melvin Calvin Melvin Ellis Calvin (April 8, 1912 – January 8, 1997) was an American biochemist known for discovering the Calvin cycle along with Andrew Benson and James Bassham, for which he was awarded the 1961 Nobel Prize in Chemistry. He spent most of h ...

. In March 1941, Melhase worked with Art Wahl. He handed her 100 grams of a uranium compound (

uranyl nitrate Uranyl nitrate is a water-soluble yellow uranium salt with the formula . The hexa-, tri-, and dihydrates are known. The compound is mainly of interest because it is an intermediate in the preparation of nuclear fuels. Uranyl nitrate can be prepa ...

) that had been neutron-irradiated by a

cyclotron A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: Janu ...

. Using a Lauritzen quartz fiber electroscope, she discovered the

Cs-137 Caesium-137 (), cesium-137 (US), or radiocaesium, is a radioactive isotope of caesium that is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nucl ...

several months later. Despite establishing herself as a promising young experimental scientist, nuclear research during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

was treated with strict secrecy and it was not publicized. Significant research on the isotope followed, but their results were not made available until after the war. Melhase received a bachelor's degree in

nuclear chemistry Nuclear chemistry is the sub-field of chemistry dealing with radioactivity, nuclear processes, and transformations in the nuclei of atoms, such as nuclear transmutation and nuclear properties. It is the chemistry of radioactive elements such as t ...

and planned to apply for graduate studies at UC Berkeley. However, the head of the chemistry department, Gilbert N. Lewis, was refusing entry to women; the last woman the department admitted had gotten married shortly after her graduation and he considered her education a "waste". She worked for the Philadelphia Quartz Company in

El Cerrito, California El Cerrito ( Spanish for "The Little Hill") is a city in Contra Costa County, California, United States, and forms part of the San Francisco Bay Area. It has a population of 25,962 according to the 2020 census. El Cerrito was founded by refugee ...

. She rejoined the

Manhattan Project The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project w ...

from 1944 to 1946. Without an advanced degree, she did not continue her career in science. Though references to her work are scant, Seaborg shares credit of his discovery of Cs-137 with her. Writing in 1961, he stated: He also wrote in 1990 that "it is appropriate to credit both G. T. Seaborg and M. Melhase for the 'birth' of cesium 137."

Personal life

Margaret was an only child, born in Berkeley, California to mother Margaret Orchard and father John Melhase, who worked as a geologist. During her time at UC Berkeley, Melhase was a member of the Berkeley Folk Dancers and edited the group's newsletter. She met mathematics professor Robert A. Fuchs at a folk dance, and the two married in 1945 and had three children. She and her husband moved to

Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the largest city in the state of California and the second most populous city in the United States after New York City, as well as one of the world' ...

. She was a supporter of social causes, organizing marches for agricultural workers and housing and aiding immigrant Laotian families in Los Angeles.

References

{{DEFAULTSORT:Melhase, Margaret 1919 births 2006 deaths 20th-century American chemists 20th-century American women scientists Manhattan Project people Nuclear chemists People from Berkeley, California University of California, Berkeley alumni Women chemists 21st-century American women Women on the Manhattan Project