As some of you probably know, the Square Kilometre Array will become the biggest radio telescope on Earth, with a collecting area of 1 square kilometre.

The construction will start in 2021 and the first light is expected to take place in 2027. It will cover the frequencies from 50 MHz to 15 Ghz.

But what I wanted to share with you guys is a new study about how far the SKA can 'listen'.

A recent study points out that the SKA could detect extraterrestrial airport radars 200 light years away.

Source: https://www.youtube.com/watch?v=ayqyb8XCtE0

What do you guys think?

200 Light Years. Not many main sequence, non binary stars within that distance. Perhaps we are talking about radar power of maybe up to 1 megawatt.

If other civilizations are much further away, then I think; as many of us have often mused: Only a high power focused beam is likely to be received as evidence of another civilization.