(1892-1965) British physicist who worked at Cambridge under Ernest Rutherford from 1920. He proved the existence of the Kennelly–Heaviside layer (now called the E layer) in the atmosphere, and the Appleton layer beyond it, and was involved in the initial work on the atomic bomb. Nobel Prize 1947.
Appleton was born in Yorkshire and educated at Cambridge. He became interested in radio as signals officer during World War I, and his research into the atmosphere was of fundamental importance to the development of radio communications.
By periodically varying the frequency of the BBC transmitter at Bournemouth and measuring the intensity of the received transmission 100 km/62 mi away, Appleton found that there was a regular fading in and fading out of the signals at night but that this effect diminished considerably at dawn as the Kennelly–Heaviside layer broke up. Radio waves continued to be reflected by the atmosphere during the day but by a higher-level ionized layer. By 1926 this layer, which Appleton measured at about 250 km/155 mi above the Earth's surface (the first distance measurement made by means of radio), became generally known as the Appleton layer (it is now also known as the F layer).
1. City in Minnesota (USA); zip code 56208.
2. City in Wisconsin (USA).
City in E central Wisconsin, US, northwest of Oshkosh, on the Fox River; seat of Outagamie country; It is a manufacturing center for paper products. It was founded 1847 and claims to have the world's first hydroelectric plant, built 1882.