Why do shortwave radio signals travel long distances?
A. Surrounding the earth is an area of charged particles called the ionosphere. Depending on input of energy from the sun and changes in the earth’s geomagnetic field, the ionosphere will usually propagate radio signals over great distances. Literally, radio signals head skyward and “bounce” off the ionosphere back to earth. At times, radio signals will make multiple “bounces” to go all the way around the world.
