The prediction by van de Hulst, (1945) and Shklovsky (1949) and the subsequent discovery by Ewen and Purcell, Muller and Oort and Pawsey in 1951 of 21 cm emission from interstellar neutral hydrogen have opened up many new fields of research in astronomy. Half of the mass of our Galaxy, in t he form of neutral hydrogen and previously undetectable, is now accessible to detailed study. Moreover, since there is negligible interstellar obscuration at radio frequencies, even the most distant parts of the Galaxy are observable. An investigation of the Doppler displacement of the line enables the emission from neutral hydrogen to be mapped in a third dimension - depth.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:602515 |
Date | January 1956 |
Creators | Davies, Rodney Deane |
Publisher | University of Manchester |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
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