James Stanley Hey (3 May 1909 – 27 February 2000) was an English physicist and radio astronomer. With the targeted application of radar technology for astronomical research, he laid the basis for the development of radio astronomy. While working in Richmond Park during the Second World War, He discovered that the Sun radiates radio waves and localised for the first time an extragalactic radio source in the constellation Cygnus. Early life and education He was born in 1909 in Nelson, Lancashire, the third son of a cotton manufacturer, which was the main industry in Lancashire. Hey studied physics at the University of Manchester, graduating in 1930, and obtained his master's degree in X-ray crystallography the next year as a student of Lawrence Bragg. Career After graduating, Hey became a teacher, and taught physics at Burnley Grammar School for some years. In 1940 Hey joined the Air Defence Research and Development Establishment's (ADRDE) Operational Research Group, later the Army Operational Research Group (AORG) after a six-week course at the Army Radio School. Hey was based at Petersham, Surrey, and later at Ibstock Place, Roehampton, Surrey. His main research site was nearby in Richmond Park. From February 1942 Hey's 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 three German warships through the English Channel, aided by enemy radar jamming from the French coast, had highlighted the problem. On 27 and 28 February 1942 Hey had reports from sites across Britain of severe noise jamming of anti-aircraft radars in the 4–8 m range. Realising that the direction of maximum interference seemed to follow the Sun, he checked with the Royal Observatory, Greenwich 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. This was the first discovery of a specific astronomical radio source. Later in 1942, G.C. Southworth in the USA also linked the Sun with radio noise, this time in the centimetre-wave region. Later, in 1944–1945, Hey used radar to track the paths of V-2 rockets approaching London at about 100 miles high, aiming to be able to predict their point of impact. He noticed spasmodic transient radar echoes at heights of about 60 miles,