Extent of human radio broadcast
ASSUMING THAT THERE ARE OTHER INTELLIGENT CIVILISATIONS OUT THERE IN THE UNIVERSE, WHAT IS THE LIKELIHOOD THAT WE’LL EVER BE ABLE TO COMMUNICATE? The key to answer this question is to look at the Drake Equation. Where N is the number of civilisations in our galaxy with which radio-communication might be possible (i.e. planets past our light cone); The DE tells you the necessary informations we need to estimate an answer for. The probability we communicate with another civilisation depends on the number of stars in our galaxy (represented by the average star-formation rate R * ), the fraction of stars with planets (f p ), the average number of planets in the Goldilock zone (n e ), the fraction of planets that develop life (f l ), the fraction of planets with life that develop an intelligent life form(f i ), the fraction of them with ability to communicate using technology (f c ) and finally the length of time this civilisation release signal into space (L). These