Astronomy Bio...Henry Norris Russell
Henry Norris Russell was born in Oyster Bay, New York on October 25, 1877. His father was a Presbyterian pastor. When he was five years old he was motivated to become an astronomer after observing the transit of Venus with his parents. His early education was at home. At the age of 12 he went to the Princeton Preparatory School and entered the College. At the age of 16 he went to Princeton University and graduated with distinction in 1897.In 1899 he received his PhD in Mathematical Astronomy from Princeton for originating a new way to determine the orbits of binary stars.
In 1903 he joined Arthur Hinks at the Cambridge University Observatory in England to work with stellar photography to develop a technique to measure stellar parallax. In 1905 Russell became Professor and Director of the University Observatory on his return to Princeton. The stellar parallax measurements were completed in 1910 and led to his discovery of the relationship between the absolute magnitudes and spectral types of stars. The Danish astronomer Ejnar Hertzsprung (born October 8, 1873) had also been working independently on developing a diagram showing the luminosity of stars in a cluster or galaxy plotted against their surface temperatures or color. The majority of stars lie on a diagonal band. The main sequence extends from hot stars of high luminosity in the upper left corner to cool stars of low luminosity in the lower right corner. The concentration of stars in certain distinct regions of the diagram indicates that definite laws govern stellar structure and stellar evolution.
By 1912 Russell showed that there was a relationship between true brightness and type of spectrum. The system of spectral classification was developed by Annie Cannon' system that also indicated surface temperature. By 1913 Russell refined the correlation and is now referred to as the Hertzsprung Russell diagram. In 1921 Russell received a Research Associate from Mount Wilson Observatory.
In the latter half of the 1920's Russell determined the profusion of elements in stars using the recently developed quantum theory. He used the profiles of absorption lines, in his analyses, to determine the relative abundance of about 50 various elements in the solar atmosphere. Russell also utilized this approach to analyze numerous stars. This research indicated that there was a very high abundance of hydrogen in both the Sun and stars. This was of great importance to our understanding of the structure and development of stars and the evolution of chemical elements. In 1929 he completed his lengthy paper on the atomic composition of the stars. He also contributed to the theory (the Vogt-Russell theorem) of stellar structure by pointing out that the physical properties of a star at each stage of its evolution can be determined from its mass, composition and age.
Russell's continual investigation of binary stars resulted in a procedure for calculating the mass of each star by studying its orbital behavior. He pioneered work on a system that utilized both the orbits and masses to compute a star's distance from Earth. Russell's research into eclipsing binary stars (were one moves in front of the other, from Earth's point of view) led to the accumulation of valuable data on variations in light emission.
Awards and Honors include the Bruce Medal (1925), Franklin Institute's Ben Franklin Medal (1934), National Academy of Sciences Henry Draper Medal (1922), a lunar crater "Russell", a Martian crater "Russell" and the minor Planet # 1762 "Russell".
A contemporary of his described him as the Dean of American Astronomers. He died at Princeton in 1957.