Towards the end of the 19th century, physicists considered radio waves to be “invisible light.” In many respects, that is exactly what radio waves are: an electromagnetic frequency, oscillation or signal outside of the visible spectrum that allows communication to occur over great distances. One of the wonders of creation is that communication of this nature is only possible due to the ionosphere—a layer of our atmosphere—above us. The waves emitted from an electromagnetic impulse are sent at the speed of light outwards and upwards, and without the ionosphere reflecting these signals back to earth, many waves would fly away into space.