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Hey, James Stanley

radio radar jamming sun

(1909–2000) British physicist: pioneer radio astronomer.

Hey studied physics at Manchester, graduating in 1930, and obtained his master’s degree in X-ray crystallography the next year. He was then a teacher of physics in a northern grammar school for some years. The Second World War began in 1939, and in 1942 Hey joined the Army Operational Research Group (AORG) after a 6-week course at the Army Radio School. His task was to work on radar anti-jamming methods; for a year German jamming of Allied radar had been a problem and the escape of two German warships ( Scharnhorst and Gneisenau ) through the English Channel, aided by enemy radar jamming from the French Coast, had highlighted the problem. In February 1942 Hey had reports of severe noise jamming of anti-aircraft radars in the 4–8 m range. Realizing that the direction of maximum interference seemed to follow the Sun, he checked with the Royal Observatory and found that a very active sunspot was traversing the solar disc. He concluded that a sunspot region, which was believed to emit streams of energetic ions and electrons in magnetic fields of around 100 G (gauss), could emit metre-wave radiation. In 1942, G C Southworth in the USA also linked the Sun with radio noise, this time in the centimetre-wave region.

Later, in 1945, Hey used radar to track the paths of V2 rockets approaching London at about 100 miles high. A problem here arose from spasmodic transient radar echoes at heights of about 60 miles, arriving at a rate of five to 10 per hour. When the V2 attacks ceased, the echoes did not; Hey concluded that meteor trails were responsible and that radar could be used to track meteor streams, and could of course do so by day as well as by night.

He went on to locate in 1946 a radio source identifiable with Cygnus A, a powerful discrete stellar radio source , in 1933, had shown that a radio source exists in our Galaxy (the Milky Way) and using his homemade equipment, had made the first contour maps of cosmic radio noise distribution in 1944 and had shown that the Sun was a radio emitter, unaware of Hey’s results of 1942, which could not be published until after the war. Jansky and Reber moved on to other work after their initial discoveries and Hey became Head of the AORG in 1949. From 1950 radio astronomy expanded enormously, in the hands of and others.

Heyer, Steven J. - Chief Executive Officer of Starwood Hotels Resorts Worldwide, Career, Sidelights [next] [back] Hevesy, Gy├Ârgy

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