Science: Kennelly-Heaviside Bulge

To explain radio, among other natural phenomena, physicists have imagined a stretchy blanket of ions encasing the Earth. This is the Kennelly-Heaviside Layer, named after Harvard's Bombay-born Professor Arthur Edwin Kennelly and England's late (1850-1925) Oliver Heaviside, bookstore keeper who for amusement invented mathematical forms to describe the behavior of alternating currents. Radio waves are presumed to reflect from the Layer much as light beams reflect from a mirror. Estimates place the Layer at 50 to 250 mi. from Earth's surface and picture it as roughly spherical.* At night the Layer...

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