Russell, Henry Norris (1877-1957), an American astronomer, influenced the growth of theoretical astrophysics in the United States. Around 1910, he and the Danish astronomer Ejnar Hertzsprung independently developed a diagram that relates the brightness of a star to its surface temperature. Research based on this diagram has helped scientists interpret the physical nature and evolution of stars. In 1929, Russell presented strong evidence that hydrogen is by far the most abundant chemical element in the atmosphere of stars.
Russell was born in Oyster Bay, New York. From 1912 to 1947, he was director of the observatory at Princeton University.
