Jansky, Karl Guthe

SUBJECT AREA: Electronics and information technology, Telecommunications

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b. 22 October 1905 Norman, Oklahoma, USA

d. 14 February 1950 Red Bank, New Jersey, USA

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American radio engineer who discovered stellar radio emission.

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Following graduation from the University of Wisconsin in 1928 and a year of postgraduate study, Jansky joined Bell Telephone Laboratories in New Jersey with the task of establishing the source of interference to telephone communications by radio. To this end he constructed a linear-directional short-wave antenna and eventually, in 1931, he concluded that the interference actually came from the stars, the major source being the constellation Sagittarius in the direction of the centre of the Milky Way. Although he continued to study the propagation of short radio waves and the nature of observed echoes, it was left to others to develop the science of radioastronomy and to use the creation of echoes for radiolocation. Although he received no scientific award for his discovery, Jansky's name is primarily honoured by its use as the unit of stellar radio-emission strength.

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Bibliography

1935, "Directional studies of atmospherics at high frequencies", Proceedings of the Institute of Radio Engineers 23:1,158.

1935, "A note on the sources of stellar interference", Proceedings of the Institute of Radio

Engineers.

1937, "Minimum noise levels obtained on short-wave radio receiving systems", Proceedings of the Institute of Radio Engineers 25:1,517.

1941, "Measurements of the delay and direction of arrival of echoes from nearby short-wave transmitters", Proceedings of the Institute of Radio Engineers 29:322.

Further Reading

P.C.Mahon, 1975, BellLabs, Mission Communication. The Story of the Bell Labs.

W.I.Sullivan (ed.), 1984, The Early Years of Radio-Astronomy: Reflections 50 Years after Jansky's Discovery, Cambridge: Cambridge University Press.

See also: Appleton, Sir Edward Victor

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