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ionosphere

(Encyclopedia)ionosphere īŏnˈəsfēr [key], series of concentric ionized layers forming part of the upper atmosphere of the earth from around 30 to 50 mi (50 to 80 km) to 250 to 370 mi (400 to 600 km) where it m...

luminescence

(Encyclopedia)luminescence, general term applied to all forms of cool light, i.e., light emitted by sources other than a hot, incandescent body, such as a blackbody radiator. Luminescence is caused by the movement ...

Van Allen, James Alfred

(Encyclopedia)Van Allen, James Alfred, 1914–2006, American physicist and space scientist, Mt. Pleasant, Iowa. A graduate (Ph.D 1939) of and professor of physics (1951–85) at what is now the Univ. of Iowa, where...

microwave oven

(Encyclopedia)microwave oven, device that uses microwaves to rapidly cook food. The microwaves cause water molecules in the food to vibrate, producing heat, which is distributed through the food by induction. A spe...

Drude, Paul Karl Ludwig

(Encyclopedia)Drude, Paul Karl Ludwig poul kärl lo͝otˈvĭkh dro͞oˈdə [key], 1863–1906, German physicist. Drude first experimented with the physical determinants of optical constants, measuring the optical c...

Fitzgerald, George Francis

(Encyclopedia)Fitzgerald, George Francis, 1851–1901, Irish physicist. Fitzgerald was born in Dublin and studied and taught at Trinity College there. He is best known for suggesting how the ether, by causing the c...

radio

(Encyclopedia)CE5 A. AM transmitter B. AM receiver radio, transmission or reception of electromagnetic radiation in the radio frequency range. The term is commonly applied also to the equipment used, especially...

Geiger, Johannes Wilhelm

(Encyclopedia)Geiger, Johannes Wilhelm (Hans Geiger) gīˈgər [key], 1882–1945, German physicist. Geiger received a doctorate in physics at Erlangen in 1906, then went to Manchester, where he assisted British c...

Lewis, Edward B.

(Encyclopedia)Lewis, Edward B., 1918–2004, American geneticist, b. Wilkes-Barre, Pa., grad. California Institute of Technology (Ph.D. 1942). After serving as a meteorologist with the U.S. Army Air Corps during Wo...

Smoot, George Fitzgerald, 3d

(Encyclopedia)Smoot, George Fitzgerald, 3d smo͞ot [key], 1945–, American astrophysicist, b. Jacksonville, Fl., Ph.D. Massachusetts Institute of Technology 1970. Smoot has been a professor at the Univ. of Califor...