Ejnar Hertzsprung


Also found in: Wikipedia.

Hertzsprung, Ejnar

 

Born Oct. 8, 1873, in Frederiksberg, Denmark; died Oct. 21, 1967, in Tølløse, Denmark. Astronomer. Member of the Dutch and Danish academies of sciences and corresponding member of the Paris Academy of Science.

Hertzsprung, who was educated as a chemical engineer, was a professor of astronomy at Göttingen, Potsdam, and Leiden. From 1935 to 1945 he was director of the Leiden Observatory. He discovered (1905, 1907) the division of stars of spectral classes G, K, and M into “giants” and “dwarfs” and the existence of a relationship between the absolute magnitude and spectral class of stars. (Subsequently this relationship was examined in detail by the American astronomer H. Russell and was named the Hertzsprung-Russell diagram.) Hertzsprung applied photography for the first time (1914-19) to the study of binary stars.

REFERENCES

Pannekoek, A. Istoriia astronomii. Moscow, 1966. (Translated from English.)
Strand, K. “Ejnar Hertzsprung, 1873-1967.” Astronomical Society of the Pacific. Publications, 1968, vol. 80, no. 472, pp. 50-56.
References in periodicals archive ?
En 1911 Ejnar Hertzsprung y Henry Norris Russell establecen la relacion entre la luminosidad y el color de las estrellas, y la expresan como una sucesion, conocida como Diagrama de Hertzsprung-Russell.
In the decade before Russell's work, Ejnar Hertzsprung (1893-1967) had studied stars and independently came to some ideas that were precursors to Russell's diagram.
In 1927 the Danish astronomer Ejnar Hertzsprung (1873-1967; Figure 13), of Hertzsprung-Russell diagram fame, was examining plates in the archives at Harvard College Observatory.
Halm was soon followed in this concept by Ejnar Hertzsprung who, in 1919, also established a relationship between these two variables [94].
The terms were conied by Danish astronomer Ejnar Hertzsprung.
The Danish astronomer Ejnar Hertzsprung (1873-1967) suggested that if a star's distance were known, one could calculate what magnitude it would have if it were some standard distance away.
Danish astronomer Ejnar Hertzsprung discovered years later that Maury's c-subdivision separated normal red stars from luminous red giants, a discovery he attributed to Maury's sharp eye in distinguishing stellar spectra.
Ejnar Hertzsprung and Henry Norris Russell independently constructed the first such plots nearly a century ago, and they are therefore today called Hertzsprung-Russell diagrams, or H-R diagrams.
Ejnar Hertzsprung noticed that the colour of Jupiter's satellite Io was orange.
Russell (1877-1957) will always be remembered for developing, independent of Ejnar Hertzsprung, the diagram that plots stellar luminosities against surface temperatures, one of the most powerful tools in astronomy.
Similarly, to understand the significance of Russell's contribution to theories of stellar evolution, we must think ourselves back not only to the time when his "giant-and-dwarf" theory was accepted but still earlier, to a time before either Ejnar Hertzsprung or Russell had recognized the existence of giants and dwarfs, and an even older theory of stellar evolution was current.