Subject: DO ALL AM RADIO WAVES REFLECT OFF THE ATMOSPHERE, OR DO SOME ESCAPE...

I have heard that since the first radio broadcasts in the early 20th c. radio 
waves have been escaping from the earth and have travelled some 80 LY 
or so by now.  But someone tells me no, because these early AM waves 
were reflected by the atomsphere back inward, while the later FM and TV 
wavelengths could escape.  I thought that  while some AM do reflect back 
down, perhaps the more vertical ones would escape (thinking of total 
internal reflection and critical angle).  Am I wrong? Thanks very mucyh

Re: DO ALL AM RADIO WAVES REFLECT OFF THE ATMOSPHERE, OR DO SOME ESCAPE...