Johan Ludvig Emil Dreyer

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Johan Ludvig Emil Dreyer

Johan Ludvig Emil Dreyer (born February 13, 1852 in Copenhagen , † September 14, 1926 in Oxford ) was a Danish astronomer and science historian. In celestial science he was best known for the NGC catalog, a directory of over 7000 star clusters, nebulae and galaxies.

Life

Dreyer's father was the officer, most recently Major General, Frederik Dreyer . His mother was his wife Ida Nicoline Margrethe, b. Randrup (born December 28, 1812 in Copenhagen; March 1, 1893 ibid).

Dreyer already demonstrated extraordinary talent in mathematics, physics and history during his school days in Copenhagen. Astronomy and the history of science were the fields in which he would later become particularly active. From 1874 he worked on the large reflecting telescope of William Parsons, 3rd Earl of Rosse , in Birr Castle, where he was intensively involved with foggy celestial objects. From 1878 to 1882 he was an assistant at the Dunsink Observatory , then was appointed director of the Armagh Observatory .

There he began work on his main work, the New General Catalog of Nebulae and Clusters of Stars (NGC). In doing so, he drew on results that he himself had already gained at Birr Castle, as well as a number of older fog catalogs (by William Herschel et al.) And the Second Armagh Catalog of Stars . The NGC published in 1888 contained 7840 entries and was later supplemented by supplements, the index catalogs I (1895) and II (1908) with a further 5386 objects. Although a number of special catalogs have since been published, the NGC has remained the reference work to this day.

From the early days of scientific astronomy, Dreyer was particularly interested in the work of his compatriot Tycho Brahe . His biography Tychos (1890) is still the standard biography of this important forerunner of Johannes Kepler . It was supplemented by the comprehensive edition of all of Tycho's works in Latin. In 1906 he published The History of the Planetary System from Thales to Kepler . In 1912 he wrote the biographical introduction to The scientific papers of Sir William Herschel . For this purpose, all of his manuscripts had to be critically examined, as well as his observation notes (which Dreyer partially supplemented with his own follow-up observations ); Added to this were the extensive correspondence and autobiographical notes Herschel made available to him by his family.

Dreyer was director of the Armagh Observatory in Northern Ireland until 1916. In 1901 he was made a knight of the Order of Dannebrog . In 1916 he received the gold medal from the Royal Astronomical Society . 1923/24 Dreyer was President of the Royal Astronomical Society .

A moon crater is named after him.

literature

Web links

Endnotes

  1. ↑ a b Dansk Biografisk Leksikon .
  2. ↑ Johan Ludvig Emil Dreyer in the Gazetteer of Planetary Nomenclature of the IAU (WGPSN) / USGS
personal data
SURNAME Dreyer, Johan Ludvig Emil
BRIEF DESCRIPTION Danish astronomer
DATE OF BIRTH February 13, 1852
PLACE OF BIRTH Copenhagen
DATE OF DEATH September 14, 1926
Place of death Oxford