With a hundred billion galaxies in the observable universe, each containing a hundred billion stars, it seems likely that intelligent life will have arisen somewhere other than the Earth. However, as most of those galaxies are so far away, we have no way of detecting the existence of life in them.

Take the galaxy NGC 7049 as an example. It lies 100 million light years away, in the constellation of Indus. That means that the light from its stars takes 100 million years to reach us. We don’t see it as it is today, but rather how it appeared at the time the dinosaurs ruled the Earth.

In the intervening time, an intelligent civilisation could have arisen in NGC 7049, much as it has on Earth. They could be there right now, but we will never know. We will never find any trace of them, even if they send us a radio message; because by the time the light images of their accomplishments and the radio signals of their messages reach us, another 100 million years will have passed.

Those hundred billion galaxies in the night sky could be teeming with intelligent life, but we are separated in time as well as in space, and the chances are we will never know them, and they will never know us.

Put simply, the Fermi paradox states that if alien civilisations exist, then at least one of them would have already made contact with us – but as they haven’t, we have to ask ourselves: where are they?

The trouble is, this is a deeply flawed argument.

How long have we had radio? A hundred years? As I write this, I’m looking at a picture of Barred Spiral Galaxy NGC 1672, a dusty whorl of several hundred billion stars lying more than 60 million light years away.

If a single civilisation arose in NCG 1672 and saw fit to send (for whatever reason) a radio signal in our direction, would we have equipment sensitive enough to receive it? And even if we did, 60 million light years is a long way. In order for us to receive it now, in the relatively short period of time since we discovered radio, they would have had to broadcast it at around the time the dinosaurs were dying off on Earth.

But what if they evolved some time in the last 50 million years? Or in the last 2 million years? We’d never know.

After all, how long have we been around, as a species? 100,000 years? What if they discovered radio a thousand years ago? Perhaps we’ll find out… in 60 million years’ time.

So, fuck the Fermi paradox. The answer to the question Where are they? is simply: A really, really long way away.

Given the vastness of the cosmos and the distances involved, expecting alien signals to have arrived in the eye-blink since we invented radio seems ludicrous and self-important.

It’s like landing a plane in Nairobi, sticking your head out of the cabin door and saying: “I see no lions, therefore lions must not exist.”

We may have to resign ourselves to the possibility that although there may be a million super-civilisations currently operating in the galaxies we see though our telescopes, we’ll never know.

Even if, for some unfathomable reason, they decided to send a signal our way, the human race would probably be long extinct by the time it arrived.