If you’ve seen this video of Earth’s place in the Universe, you’ll have already seen the distance our first radio broadcasts have travelled. You’ll also have seen the huge amount of satellites buzzing around the planet, surrounding us with digital noise.
The founder of the Search for Extra-terrestrial Intelligence (SETI), Dr Frank Drake, says that the chances of alien life discovering our planet are diminishing, in the wake of the digital revolution. Apparently, phasing out analogue transmissions from television, radio and radar is making our planet electronically invisible from outer space.
While old style signals used to spread out millions of miles into outer space, even reaching some distant stars, digital transmissions are much weaker and therefore are less easy to detect by extra-terrestrial life forms.
The earth used to be surrounded by a 50 light year wide shell of radiation, with old-style television transmissions generating around one million watts, but with satellites aiming much of their transmissions towards Earth now virtually no radiation is escaping into outer space.
“Now the actual amount of radiation escaping is about two watts, not much more than you get from a cell phone. If this continues into the future, very soon our world will become undetectable.”
Dr Drake said he remained convinced that intelligent life does exist somewhere in the universe but suggested it was likely to be much more advanced than here on earth. What an irony it is, that in our efforts to improve our own communication networks we may already have cut ourselves off from the rest of the Universe.