Naked Science Forum

General Science => General Science => Topic started by: Unseen Perspective on 05/08/2022 19:38:26

Title: Why can't radio waves pass through the ionosphere, but a spaceship can?
Post by: Unseen Perspective on 05/08/2022 19:38:26

Radio waves can pass through solid objects like wood and concrete but not the ionosphere? How is it that a solid object can pass through something that and a radio wave cannot?

Title: Re: Why can't radio waves pass through the ionosphere, but a spaceship can?
Post by: alancalverd on 05/08/2022 20:02:37

The clue is in the name - ionosphere. Ionised air is an electrical  conductor and acts to some extent as a "short circuit" to electromagnetic radiation, but to a solid object it is just "thin air".

Obviously most em radiation does pass through the ionosphere (hence sunlight, radiotelescopes, and communication with spacecraft) but at some frequencies and angles of incidence it acts like a mirror.