10 Wildest Tries to Contact Aliens

reply to post by Astyanax


Forgive my ignorance, but how is it expanding at the speed of light? dont you mean the speed of sound?

reply to post by chaztekno

First of all, well done for asking. When in doubt, always ask.

The answer: no, I mean ‘at the speed of light’.

Radio waves, just like visible light, are a form of electromagnetic radiation.

The way radio waves carry sound is by encoding information about the amplitude (loudness) and frequency of the sound (something called the acoustic waveform) ‘inside’ the radio wave. This information is encoded as ‘modulations’ or variations in the amplitude (intensity) or frequency of the radio wave. AM radio uses amplitude modulation (that’s what the letters stand for); FM radio uses frequency modulation.

Your radio is a decoder that reconstructs the information encoded into the radio waves and turns them back into sound. These come out of the radio loudspeaker at... the speed of sound.

How Radio Works

reply to post by Astyanax


Very informative post Asty...I had no idea that our radio waves were that far by now...81 light years is quite far for us...but in the scope of the universe it's only in our back yard.