The Bruce Medalists


  Photo 1961, courtesy Observatories of the Carnegie Institution of Washington
Paul Willard Merrill
15 August 1887 1946 Bruce Medalist 19 July 1961

Paul Merrill was born in Minneapolis but moved to California before high school. He earned his A.B. in 1908 at Stanford University and his Ph.D. in 1913 at the University of California, spending equal amounts of time at Berkeley and the Lick Observatory. After three years at the University of Michigan, he joined the National Bureau of Standards, where he worked on aerial photography in the visible and infrared during World War I. He later proposed doing infrared astronomy from airplanes. In 1919 he joined the staff of the Mt. Wilson Observatory, where he continued his research until well after his 1952 retirement. He was a spectroscopist who studied peculiar stars, especially long-period variables. He also investigated the interstellar medium and performed pioneer spectral research in the infrared. His greatest discovery came shortly before retirement, when he identified lines of technetium in R Andromedae and other S-type stars. Since this element has no stable isotopes, Merrill’s discovery is taken as evidence for its recent production in the stars, and thus for the existence of the s-process of nucleosynthesis.

Presentation of Bruce medal
Neubauer, F.J., PASP 58, 81-85 (1946).

Other awards
American Astronomical Society, Henry Norris Russell Lectureship, 1955.
National Academy of Sciences, Henry Draper Medal, 1945.

Some offices held
American Astronomical Society, President, 1956-58.
Astronomical Society of the Pacific, President, 1927.

Biographical materials
Wilson, O.C., Biographical Memoirs of the National Academy of Science 37, 237-66 (1964) (pdf).

Joy, A.H., PASP 74, 41-43 (1962).
Joy, Alfred H., QJRAS 3, 45-47 (1962).
More obituaries

AIP Center for History of Physics
Caltech Archives

Named after him
Lunar crater Merrill
Minor Planet #11768 Merrill

More references

The Bruce Medalists

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