Henry Norris Russell ForMemRS HFRSE FRAS (October 25, 1877 – February 18, 1957) was an American astronomer who, along with Ejnar Hertzsprung, developed the Hertzsprung–Russell diagram (1910).

From 1903 to 1905, he worked at the Cambridge Observatory with Arthur Robert Hinks as a research assistant of the Carnegie Institution and came under the strong influence of George Darwin.

were largely determined by the star's mass and chemical composition, which became known as the Vogt–Russell theorem (including Heinrich Vogt who independently discovered the result).

Russell dissuaded Cecilia Payne-Gaposchkin from concluding that the composition of the Sun is different from that of the Earth in her thesis, as it contradicted the accepted wisdom at the time.

In his paper Russell credited Payne with discovering that the Sun had a different chemical composition from Earth but never shared the rewards of the fame he readily accepted for her work which he’d failed to recognize until years later.