In the latter part of the nineteenth century electricity and magnetism were a prime area of research in Europe. In 1887, Heinrich Hertz in Germany was the first to realize the significance of the behavior of radio waves. Hertz found that, like most electromagnetic waves, radio waves could be deflected and reflected by certain materials. Physicists knew that radio waves traveled at a constant 298,051 km/s (186,282 mi/s). If the returning radio waves arrived one second after leaving, then the reflecting object was 149,025 km (93,141 mi) away. The technology that used this principle was developed during the 1930s by the British team led by Sir Robert Watson-Watt, who called it RAdio Detection and Ranging, or RADAR. It was incredibly useful in 1940, when Britain was at war with Germany, as it enabled the British air force to know in advance the position of enemy aircraft even if they were invisible due...