On September 6, 1892, English physicist Sir Edward Victor Appleton was born. Appleton won the Nobel Prize in Physics in 1947 for his seminal work proving the existence of the ionosphere during experiments carried out in 1924.
Edward Victor Appleton attended St. John’s College, Cambridge where he earned his B.A. degree in Natural Science and already won the Wiltshire Prize in 1913 and the Hutchinson Research Studentship in 1914. During World War I, Appleton joined the West Riding Regiment and later moved on to the Royal Engineers before returning to Cambridge in order to research on radio waves.
It is believed that in 1919, Appleton first devoted himself to scientific problems in atmospheric physics. He was appointed assistant demonstrator in experimental physics at the Cavendish Laboratory and became sub-rector at Trinity College two years later. Starting from 1924, Edward Appleton was appointed Professor of Physics at London University. In the same year, he started a series of experiments proving the existence of the layer in the upper atmosphere called ionosphere. The research was conducted in cooperation with the British Broadcasting Corporation. The Bournemouth transmitter shot waves up to the layer in order to find out if they were reflected by it and came back. Fortunately for Appleton and his research team, the experiment was successful as the reflection was proven. Also, it was then possible to measure the time taken by the waves to travel to the upper atmosphere and back by only a slight change of wavelength. The layer’s height (60 miles above ground) was successfully determined. The used method is called “frequency-modulation radar” on this day. Appleton’s research significantly advanced radio research and broadcast. In 1926, Appleton discovered a further atmospheric layer 150 miles above ground, higher than the Heaviside Layer and electrically stronger. This layer, named the Appleton Layer after him, reflects short waves round the earth. In 1947, Edward Appleton received the Nobel Prize in Physics and was awarded the Medal of Merit among further awards.
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