Dr Frank Drake, the founder of Search for Extra-terrestrial Intelligence (SETI), 50-years ago told a meeting at the Royal Society earlier this week that the phasing out of analogue transmissions from television, radio and radar was making our planet electronically invisible from outer space.
Analogue 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.
He said 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 he said with satellites aiming much of their transmissions towards earth now virtually no radiation was escaping into outer space.
He explained: "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."
This may not be a bad thing if our neighbours include the Borg. On the other spare a thought for the disappointed aliens who will no longer be able to tune into Coronation Street... On the other hand...