Sir Edward Appleton was a British physicist born in 1892 who discovered the ionosphere through experiments using radio signals. He served in WWI and studied physics at Cambridge University. In 1924, his experiments receiving radio signals from the BBC at different times of day led him to discover the ionosphere, which reflects radio waves and enables long-distance radio communication. He received the 1947 Nobel Prize in Physics for his discovery of the ionosphere.

1. September 6, 1892~April 21, 1965
Discoverer of the ionosphere
“I rate enthusiasm even above professional skill.”
~Sir Edward V. Appleton
Circa 1935

2. • Nationality: British
• Born in Bradford, United Kingdom
• During WWI, he served in the Royal Engineers
• Studied natural sciences at Cambridge University
• Returned to Cambridge after war, researched atmospheric physics
(mainly using radio waves)
• In 1924, he began research into the strength of radio signals received at
Cambridge University from the BBC station in London.
• He discovered that strength of the signal was constant during day but
varied during night (Cambridge receiving 2 waves: 1 traveling directly
and other reflected off the atmosphere)
• He conducted experiments using the BBC transmitter to prove the
existence of reflecting layer, its position, and height above the ground.
• In 1926, he discovered another layer, about 250-350 km high, reflecting
back shorter wavelengths in the day and night and reflected them back
with greater strength than Heaviside layer. He realized that this was the
layer responsible for reflecting short wave radio round the world
(“Appleton layer”) that enables communication with Australia and
America
• Died in Edinburgh, Scotland

4. Positions held:
• Appointed Secretary of Department of Scientific and Industrial research
• Appointed assistant demonstrator in experimental physics at the Cavendish
Laboratory in 1920
• Became a professor of physics at London University in 1924
• Returned to Cambridge as professor of natural philosophy in 1936
• Knighted in 1941
• Principal and Vice-Chancellor at University of Edinburgh and held the
position till death.
Awards:
• Received Nobel Prize for Physics in 1947

5. "Edward V. Appleton Biography." Nobelprize.org. Web. 09 Oct. 2010.
<http://nobelprize.org/nobel_prizes/physics/laureates/1947/appleton-
lecture.html>.
"Historic Figures: Sir Edward Appleton (1892 - 1965)." BBC. Web. 09 Oct. 2010.
<http://www.bbc.co.uk/history/historic_figures/appleton_edward.shtml>.
"Ionopheric Propagation Explained." Chariot. Web. 09 Oct. 2010.
<http://users.picknowl.com.au/~wavetel/propagation.htm>.
"The Nobel Prize in Physics." Starts With A Bang! Web. 09 Oct. 2010.
<http://startswithabang.com/?p=982>.
"Sir Edward Appleton Quotes." ThinkExist.com. Web. 09 Oct. 2010.
<http://thinkexist.com/quotes/sir_edward_appleton/>.
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