Raymond Smith Dugan
At this time, the Heidelberg Observatory was under Max Wolf, a center of the asteroid observation and discovery. During his time there Dugan discovered 16 asteroids.
In 1905 he went back to the U.S. and worked at Princeton University. In 1908 he became an assistant professor, in 1920 professor. In 1927, he co-authored with Henry Norris Russell and John Quincy Stewart an influential two -volume work entitled Astronomy: A Revision of Young's Manual of Astronomy ( Ginn & Co., Boston, 1926-27, 1938, 1945), which for over two decades became the astronomical standard work. The first volume deals with the solar system, the second with astrophysics and stellar astronomy.
Dugan died in 1940 after a long illness. His wife, with whom he had been married since 1909, and two adopted children survived him.