21-centimetre radiation

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21-centimetre radiation: Facts & Related Content

Written and fact-checked by The Information Architects of Encyclopaedia Britannica

Facts

Also Known As	hydrogen line

Topics

hydrogen cloud radio emission blackbody radiation synchrotron radiation

Key People

E.M. Purcell

American physicist

Hendrik Christoffel van de Hulst

Dutch astronomer

Quiz

Nicolaus Copernicus. Nicolas Copernicus (1473-1543) Polish astronomer. In 1543 he published, forward proof of a Heliocentric (sun centered) universe. Coloured stipple engraving published London 1802. De revolutionibus orbium coelestium libri vi.

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