Astronomy Bio...Joel Stebbins
Joel Stebbins was born on July 30, 1878, in Omaha, Nebraska. From an early age he was interested in astronomy, and chose to major in the subject at the University of Nebraska, where he received his BA in 1899. From 1901 until 1903 he worked at the Lick Observatory, where he earned a PhD. He then became an instructor of astronomy at the University of Illinois and in 1904 was made an assistant professor. After a year's sabbatical at the University of Munich (1912 - 1913), he became a professor of astronomy at the University of Illinois and was made director of the University Observatory. In 1922 Stebbins became director of the Washburn Observatory and professor of astronomy at the University of Wisconsin.
Although he retired as professor emeritus in 1948, he continued to be an active researcher at the Lick Observatory until 1958. Stebbins was a member of the National Academy of Sciences, the American Association for the Advancement of Science and other prominent scientific organizations. In 1915 he received the Draper Medal of the National Academy of Sciences, the Gold Medal of the Royal Astronomical Society in 1950, and other honors. He died in Palo Alto on March 16, 1966.
Stebbins' earliest astronomical research involved spectroscopy and photometry. In 1906 he began attempting to use electronic methods in photometry. Initially he could study only bright objects, like the Moon, and had some encouraging results. He devoted most of his time from 1909 to 1925 to improving the photoelectric cell and used it to study the light curves of eclipsing binary stars.
With the Increased sensitivity of the device, it was used to measure the light of the solar corona during total eclipses. Although there was no detectable variations in the light output of the Sun, Stebbins discovered that he was able to observe variations in the light of cooler stars.
During the 1930s he applied his photoelectric research to the problem of the nature and distribution of interstellar dust and its effects on the transmission of stellar light. He analyzed the degree of reddening of the light of hot stars and of globular clusters. Through his discoveries, he contributed to an understanding of the structure and size of our Galaxy. Stebbins tried to determine whether interstellar material absorbed light of all wavelengths equally. He found that over a range from the infrared to the ultraviolet absorption was constant, but the absorption of ultraviolet light itself was less strong. His work included studies of the magnitudes and colors of other galaxies utilizing photoelectric equipment.
He demonstrated that his method was much more accurate than those that trusted the eye or photography. The use of the photomultiplier extended, even further, the usefulness of his technique.