RUSSELL, HENRY NORRIS 1877-1957
Astronomer
A Princeton Professor
Henry Norris Russell was born at Oyster Bay, New York, on 25 October 1877. He was educated at home by his mother, an accomplished mathematician, and his father, a Presbyterian minister, until the age of twelve. At nineteen he graduated from Princeton insigne cum laude, the highest academic honor awarded at the university. Two years later he earned the Ph.D. in astronomy at Princeton for research on the orbits of binary stars. After a period of illness Russell continued his studies at Kings College, Cambridge University (1902-1904), where he did research at the Cavendish Laboratory. Along with Arthur R. Hinks, Russell developed a method for determining stellar parallax from photographic plates. Their technique enabled astronomers to determine more accurately the distances to far-off stars. In September 1904 Russell, again taken ill, returned to Princeton, where in 1905 he was appointed instructor of astronomy. He became professor of astronomy in 1911 and the following year was made director of the university's observatory. He remained at Princeton until he retired in 1947. Following his retirement he continued his research at the Lick Observatory and at Harvard.
Hertzsprung-Russell Diagram
Russell's most acclaimed achievement was the charting of stellar evolution. Drawing on the work of several astrophysicists, especially that of Danish astronomer Ejnar Hertzsprung, he published his famous conclusions on the origin and evolution of stars in 1913. Adopting Hertzsprung's insights into dwarf and giant stars, Russell challenged the accepted paradigm of stellar development, which held that stars evolved from blue (hot) to red (cool) stars. Russell asserted instead that red stars represented both the beginning and the ending of stellar evolution. Collecting data on hundreds of stars, Russell was able to demonstrate that when the absolute magnitude of stars was plotted against their spectral class, most stars fell on an S-shaped curve that he called "the main-sequence." Russell maintained that initially stars would heat up and contract, while later in their life cycle they would expand and cool The Hertzsprung-Russell diagram remains the basis for astronomers' understanding of stellar origin and evolution.
Versatile Scientist
In 1912 Russell published the first analysis of light variation in eclipsing binary stars. From 1914 to 1921 he published papers on the orbits and masses of many binary stars. During World War I he worked to improve aircraft navigation for the Bureau of Aircraft Production of the army's Aviation Service. In the 1920s Russell's study of the absorption-line spectra of the sun led to the accurate hypothesis that hydrogen is the main element in stars. He was also able to analyze correctly many gases in the solar atmosphere. In 1927 he published a book of philosophical and religious speculation, Fate and Freedom, based on a series of lectures in religion he delivered at Yale University. Russell also studied the age of the Earth by analyzing radioactive uranium as well as thorium and lead in its crust, estimating the planet's age to be between two and eight billion years old.
Celebrated Career
Russell published hundreds of scientific papers during his career, A member of many scientific societies, he was the president of the American Philosophical Society (1931-1932), the American Association for the Advancement of Science (1933), and the American Astronomical Society (1934-1937). His most famous book is The Solar System and Its Origins (1935), a classic in the field. Upon his death in 1957 Russell was hailed as "the most eminent and versatile theoretical astrophysicist in the United States if not in the world."
Sources:
James B. Kaler, Stars (New York: Scientific American Library, 1992);
Henry Smith Williams, Great Astronomers (New York: Simon & Schuster, 1930).
