So you know the Great Filter, right?
It’s what happens when you look up at the stars and ask “Where the fuck is everyone”.
There are so many planets out there, yet it’s radio silent. The intelligent life to planet ratio is really, bad. So far we’re the only ones.
You gotta ask, why?
Enter, the Great Filter. Something, at some point in the pipeline, prevents planets from developing and maintaining intelligent life capable of electromagnetic communication.
We don’t know what it is. Maybe it’s a quirk of chemistry that makes the chance of multicellular life forming ridiculously low. Maybe it’s a quirk of biology that makes sapience incredibly rare. Maybe it’s a hyper intelligent space worm that eats any civilisation that makes too much noise. Maybe it’s runaway climate change.
The thing is, we really don’t want to be on the wrong side of that filter, because that suggests that an imminent demise is in our civilisation’s future. And with every discovery of non-intelligent life on other planets, it becomes increasingly likely that we’re on the wrong side of that filter.
Enter, the recent discovery of life on Venus. It means that we’re much more likely to be on the wrong side.
But, watching that debate tonight, I began to feel a sense of relief. At least if we’re on the wrong side of the filter, it’s not as though we’re wasting a once-in-a-galaxy chance. We’re just yet another civilisation that failed to get past that filter. I can live with being unexceptionally mediocre.
We don't have any evidence of this. It could in fact be really good, at least in terms of planets that have the conditions for sustaining animals of any sort.
I think the more likely answer is one of two things:
Sending communications between planets is really fucking difficult and takes a really long fucking time. Literally millions of years. It just hasn't happened yet towards Earth or it isn't possible for intelligent life.
World ending events are not unheard of even on our planet and it's possible they're even more common on other planets. Even if intelligent life is common, perhaps it gets reset quite frequently too. Meaning that even though intelligent life is common, the overlap between our intelligent life and that of another planet could be mismatched by a million years or more very easily.
Also, even though we "listen" for alien life, we have a pretty narrow range of coverage and not the best tools for doing it and may not even be looking for the right things.