Stebbins, Joel (1878-1966)

US astronomer, the first to develop the technique of electric photometry in the study of stars.

Stebbins was born in Omaha, Nebraska, and studied at the universities of Nebraska, Wisconsin, and California. He was professor at the University of Illinois 1913-22 and at Wisconsin 1922-48, as well as director of the Washburn Observatory. He continued research at the Lick Observatory until 1958.

In 1906 Stebbins began attempting to use electronic methods in photometry. At first only the brightest objects in the sky (such as the Moon) could be studied in this manner. From 1909 to 1925 he devoted much of his time to improving the photoelectric cell and using it to study the light curves of eclipsing binary stars. As the sensitivity of the device was increased, he could observe variations in the light of cooler stars.

During the 1930s Stebbins applied photoelectric research to the nature and distribution of interstellar dust and its effects on the transmission of stellar light. He analysed the degree of reddening of the light of hot stars and of globular clusters. His discoveries contributed to an understanding of the structure and size of our Galaxy.