Johan Dreyer Irish astronomer of Danish origin. Date of Birth: 13.02.1852 Country: Ireland

Content:

1. Johan Ludvig Emil Dreyer: A Danish-Irish Astronomer
2. Move to Ireland
3. Observatory Roles
4. British Citizenship and Later Years
5. Presidency of the Royal Astronomical Society
6. Scientific Contributions
7. He also authored a biography of Tycho Brahe.

Johan Ludvig Emil Dreyer: A Danish-Irish Astronomer

Early Life and Education

Johan Ludvig Emil Dreyer was born on October 13, 1852, in Copenhagen, Denmark. His father, Christian Emil Dreyer, served as Denmark's Minister of War. Dreyer received his education in Copenhagen.

Move to Ireland

At the age of 22, Dreyer left Denmark for Ireland to serve as an assistant to Lord Rosse, the son and heir of the builder of the "Parsonstown Leviathan" telescope.

Observatory Roles

In 1878, Dreyer transferred to the Dunsink Observatory. In 1882, he joined the Armagh Observatory, where he served as Director until 1916.

British Citizenship and Later Years

In 1885, Dreyer became a British citizen. He spent his later years in England and died in Oxford on September 14, 1926.

Presidency of the Royal Astronomical Society

Dreyer served as President of the Royal Astronomical Society from 1923 to 1924.

Scientific Contributions

Dreyer's most significant scientific work is the New General Catalogue of Nebulae and Clusters of Stars, which he cataloged by number in 1888. This catalog is still used today and has been expanded by two index catalogs (IC I in 1895 and IC II in 1908).

He also authored a biography of Tycho Brahe.

Honors and Recognition

Dreyer was awarded the Gold Medal of the Royal Astronomical Society in 1916. A crater on the Moon is named after him.

Astronomy

Christoph Scheiner	Henri Andoyer	Pierre-Jules-Cesar Janssen
William Robert Brooks	Willem Hendrik van den Bos	Guillermo Haro