George Ellery Hale

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George Ellery Hale 1905

George Ellery Hale (born June 29, 1868 in Chicago , Illinois , † February 21, 1938 in Pasadena ) was an American astronomer . It is associated with the era of large mirror telescopes and significant advances in solar research and in models of stellar evolution . He worked closely with telescope maker George Willis Ritchey .

Live and act

Hale, born in Chicago in 1868 and from a well-to-do family, observed the splitting of absorption lines ( Zeeman effect ) while observing the solar spectrum and demonstrated that the sunspots are locations of strong magnetic fields . At the age of 21 he developed the spectroheliograph as a student at the Massachusetts Institute of Technology (MIT) around 1890 (at the same time as Henri-Alexandre Deslandres ) . This instrument was soon used worldwide to study the sun in narrow spectral ranges.

He studied at MIT, was at the observatory of Harvard College in 1889/90 and in Berlin in 1893/94. In 1890 he ran his own observatory (Kenwood Astrophysical Observatory) on the family seat in the Chicago borough of Kenwood. From 1891 to 1893 he was professor of astrophysics at Beloit College in Beloit (Wisconsin) .

Hale was appointed to the University of Chicago in 1892 , where he was associate professor until 1897 and then professor until 1905. Since it by a new 40 in the same year tariff - Lens heard he related to the construction of a large observatory from. Hale managed to find a wealthy sponsor from Chicago for this: Charles Yerkes . In 1897, for example, the huge refractor with a 102 cm aperture at the new Yerkes Observatory became the largest telescope in the world at the time . It is still the largest lens telescope ever built.

Hale was an extremely energetic man who founded other observatories for his research, equipped with ever larger telescopes and the latest equipment. In Pasadena he had his own solar observatory ( Hale Solar Laboratory ). He played a leading role in building the Caltech .

As Secretary for Foreign Relations of the National Academy of Sciences , Hale nominated the German physicist Johannes Stark for the Nobel Prize in Physics in 1914 and 1916, regardless of the First World War . At Hale's instigation, the National Research Council was founded in 1916 , for which Hale worked together with Robert Andrews Millikan until 1917 . Hale's goal was that scientists instead of normal military service were used according to their qualifications as scientists.

Hale began promoting the construction of a giant telescope mirror in 1927. In 1928 he was able to convince the President of the Rockefeller Foundation of this huge investment in science. The reflecting telescope on Mount Palomar was completed in 1947 . With a primary mirror measuring 200 inches (5 meters), it was the largest telescope in the world until 1975. Even today it is the largest telescope with an equatorial mount .

Mount Wilson has a reflecting telescope with a primary mirror 2.5 meters in diameter, which was built under the direction of George Willis Ritchey. Edwin Hubble was able to detect the first single stars in the Andromeda nebula around 1923 and discover the expansion of the universe . Until the Palomar telescope was built, this telescope was the largest in the world.

Hale had severe mental health problems that also forced him to resign from his post as director of Mount Wilson.

In 1894 he founded the Astrophysical Journal, of which he was editor from 1895. From 1892 to 1895 he was co-editor of Astronomy and Astrophysics.

He was a foreign member of the Académie des Sciences (1919) and the Royal Society (1909).

The two Hale observatories on Mount Wilson and Mount Palomar were named after him in 1970 .

The moon crater Hale is named after him and the inventor William Hale . The Hale crater has been named after him since 1973 . The asteroid (1024) Hale is also named after him.

Awards

Web links

Individual evidence

  1. Biography of George Ellery Hale in the Encyclopedia Britannica
  2. ^ Hale On the Probable Existence of a Magnetic Field in Sun-Spots , The Astrophysical Journal , Volume 28, 1908, p. 315
  3. Deutscher Reichsanzeiger No. 231 of September 30, 1908
  4. Johannes-Geert Hagmann: How physics made itself heard - American physicists engaged in "practical" research during the First World War . Physik Journal 14 (2015) No. 11, pp. 43–46.
  5. Sheehan, William; Osterbrock, Donald E .: Hale's "Little Elf": The Mental Breakdowns of George Ellery Hale . In: Journal for the History of Astronomy . No. 5 , 2000, pp. 93–114 , doi : 10.1177 / 002182860003100201 , bibcode : 2000JHA .... 31 ... 93S .
  6. Entry on Hale, George Ellery (1868 - 1938) in the archives of the Royal Society , London
  7. ^ Member History: George E. Hale. American Philosophical Society, accessed September 19, 2018 .
  8. ^ Fellows Directory. Biographical Index: Former RSE Fellows 1783–2002. (PDF) Royal Society of Edinburgh, accessed December 14, 2019 .