🚀 go-pugleaf

Now wait a minute, wait..wait..wait..

Most people, nearly all, will tell you that, yes, they do
believe that there are other civilizations outside of the
Earth. That, space is just so big, so infinite is size that
no matter how small we make the odds we are left with huge
numbers of inhabited worlds.

Think of this:  If all we do is assume that maybe there's
one civilization to arise, on average, for every single
GALACTIC CLUSTER, that still leaves us with half a trillion
alien civilizations.

Oh. A "Galactic Cluster" is literally what it sounds like,
which is to say a cluster of galaxies.

Yes galaxies appear to cluster in groups.

We're talking 100, maybe even 1,000 galaxies per cluster,
and if we assumed that they average even just one single
intelligent species per cluster, we're looking at half a
trillion or more alien civilizations surrounding us...

So the numbers are BIG.

This same argument or "Logic" can be applied to alien craft.

NOTE:  "Alien craft" doesn't have to be manned. We've sent
plenty of tech out into space yet, apart from our own moon,
we don't as a rule send people. Just machines.

Next...

Already we here on the planet Earth can detect "Biosignatures"
on other worlds more than 100 light years away.

A "Biosignature" would be anything placed in the atmosphere by
life. Oxygen, here on earth, comes from life. Methane, here on
Earth, is likewise a biproduct of life... on & on & on...

So the point is that we can identify "Biosignatures" out beyond
100 light years from us, already, yet we haven't even been in
the exoplanet game for 40 years yet!

If an alien species is exactly as technologically advanced as
we are, and within 100 light years, they know that we're here.

They know that there's life on this Earth.

Now imagine if they are as advanced as we are -- not any more
high tech then us here on Earth -- but their priorities are
completely different. Maybe what we invest into the military
is what they invest into space exploration. In which case, they
might've found us a decade or more ago!

The point is that we don't have to imagine Star Trek or a
Flash Gordon scenario here. A civilization's priorities may
be a larger factor in their ability to spot us then even
there level of technology. They might be a few decades behind
us, but simply spent the bucks where we wouldn't...

Yeah space is huge and they could be looking but still managed
to miss us, or haven't gotten around to us yet, more likely,
but if they exist they can spot us. They can know life is here.

That's it.

The planet has been broadcasting the fact that there's life
down here -- via biosignatures -- for BILLIONS of years already,
so time doesn't even seem to be a factor....

So, let's guesstimate here:  If we've been visible for billions
of years, and they could exist anywhere out beyond 100 light
years in any direction, what are the odds that someone sends a
probe to inspect this life-bearing world that they see?

Well. Even if it only happens once in a million years, there's
been over 60 since the dinosaurs went extinct. There's been
some 500 or more since the Cambrian explosion. There's been two
to three since the genus Homo (humans) evolved...

At once every 100 million years there's been at least five since
the Cambrian Explosion.

At once every billion years there's been 2 since the Great
Oxidation Event...

It's just one of those things where no matter how big we make
the numbers, there's been so much time and space is so
incomprehensibly large that we still have alien craft buzzing
the earth.





















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https://jtem.tumblr.com/tagged/The%20Book%20of%20JTEM/page/5