One of the most commonly used tropes in science fiction is that of the notion of an alien
invasion.
Hundreds of variations on this theme have been written over the years, typically focusing
on us having something that is useful enough for aliens to expend the time and energy in
conquering earth.
While all of this makes for a good story, it doesn’t make for a good reality.
After all, this planet has been here for 4.5 billion years and does not appear to have
ever been invaded.
Why that is is anyone’s guess, but here are ten possible reasons why aliens might
not invade earth.
10.
The Galaxy has Nothing But Room
Everywhere we look in the Milky Way we see star after star to the tune of billions and
so far not one, other than our own solar system, has ever been shown to be inhabited by a civilization.
Some of them may yet be, but we see no evidence of Kardashev type III galactic empires present
in this, or any other galaxy.
In fact, so far, we have yet to see even a Kardashev Type II civilization.
This could change, but the one thing that can be said is that there appears to be millions
of stars that are not being used for anything.
Great nebulas rich in raw materials are not rare, but seem to only be forming stars rather
than being harvested by someone.
Often in science fiction, raw materials are used as a justification for invasion.
But in the great scheme of things, there appears to be no one picking the low hanging fruit
much less looking at relatively sparse sources of raw materials such as our star system.
9.
We Don’t Make for Good Slaves
Another common theme found in science fiction alien invasions is a desire for slave labor.
This is not without precedent, a number of human cultures have employed it.
But those cultures also were dealing with primitive technologies and required human
labor.
The problem is, biological human labor will some day go obsolete.
It already is in our world as technological unemployment increasingly becomes a problem.
Simply put, robots can be better at it almost anything we do, if they become advanced enough.
Any civilization in the galaxy capable of long-distance space travel and the technologies
implied by it would likely have robotics so advanced that no biological labor at all would
be needed.
And besides, as long as you keep the technology under control and don’t go all crazy with
artificial intelligence, mindless robots will never revolt.
Humans would every chance we could making us useless to the aliens.
8.
Our Planet is Fundamentally Useless
Yet another common theme within invasion sci fi is the idea that earth, or we, have something
an alien civilization wants.
This could be something like water, or even information, and they invade to get it from
us.
Trouble is, we don’t have much of anything.
Earth is nothing special, it’s made up of the same materials that we see out in the
galaxy at large.
Immense quantities of water exist in the universe, both in frozen and liquid form.
In fact, it appears to be common in our own solar system, you see it almost everywhere.
It’s much the same for information.
What could we tell the aliens that they didn’t already know or couldn’t learn on their
own?
The truth is, not much.
About the only information we have unique to ourselves is information about ourselves.
It’s highly unlikely that an alien civilization would expend invasion level resources on finding
out what a potato chip is.
7.
We Are Very Likely Not Tasty
Speaking of foods, take a look at your planet.
Surrounding you are millions of species, from bacteria to plants to animals.
Now, ask yourself.
How many of them would you eat?
Out of all life on this planet, we eat only a comparative handful of species.
Many are fundamentally unpalatable, such as most plants, but many are outright poisonous
causing anything from intestinal discomfort to death.
Now imagine an alien species with radically different biochemistry.
They would have evolved on a world eating flora and fauna unique to that planet.
It’s unlikely that anything here, or anything they might have, would be appealing to either
species and there’s no guarantee that they even eat in the same way we do.
Life here doesn’t always, so the idea of aliens eating us is a hard sell in much the
same way as an oak tree munching on pineapples would be.
And, we might even be poisonous.
6.
Our Genetics Aren’t Useful
Another culturally pervasive notion is that of mating with an alien.
From Captain Kirk’s green lady to The Alien’s xenomorph facehuggers using us as a reproductive
resource, there are many takes on this idea.
But in reality, genetics doesn’t really work that simply.
The vast majority of species on earth can’t reproduce with each other despite being related,
there are no jelly-fish bonobo hybrids slithering about.
And while parasitic types of reproduction do occur, yay for the xenomorphs, that’s
using a host as grounds for reproduction, not reproduction with a mate.
Genetic compatibility with a species you have zero relation to, something truly alien from
another world, would be so unlikely that lottery odds are better.
But even if there was compatibility, would there be attraction?
Kirk’s green lady was a human in green makeup, remember.
Alien life would be alien, and might be about as attractive as kissing a facehugger.
But there’s an even deeper problem hiding within this.
Each day we learn more about genetics and DNA.
While we don’t yet know everything, there will come a time when we have a full command
of that science.
It’s likely that an alien species capable of space travel would have that as well.
Even if they didn’t have DNA of their own, which is unlikely, it’s still just a matter
of chemistry.
As a result, they could probably do whatever they wanted with genetics, possibly building
DNA strands from the ground up to build any kind of programmable creature they wish.
If so, what use would they have for our natural and rather messy DNA?
5.
The Human and the Ant
Ants usually go unnoticed.
Unless they bother us, we pass by their dwellings and rarely pay them any mind.
Even less do we stop and speak to them.
Only a scientist studying ants would take further interest, but even then they typically
don’t plant a flag in the ant hill and declare themselves the new queen.
We have to consider that aliens may have no interest in us at all.
For anything.
They may be a billion years more advanced and messing around with us might be no different
than junking your idea for a Caribbean cruise in favor of trekking to a plain in Africa
to study one specific ant hill that you once saw a picture of that may or may not even
still be there.
In short, why would you invade an ant hill?
4.
We’re More Interesting Alive Than Dead
Or say they are interested.
Say they are consummate scientists and historians interested in all aspects of alien cultures.
This isn’t unreasonable, we certainly would be.
And, well, have to say it, an alien ant hill would still be extremely interesting to us
to the point that we would go to great lengths to study it.
But what we likely wouldn’t do is willfully exterminate it in order to study it.
Such things happen on earth, but for very different reasons than scientific curiosity.
As a result, the scholar aliens probably would not declare themselves our overlords and plant
a flag in our cosmic ant hill, but instead they might just show up, enter orbit and tell
us not to mind them, they just want to watch us.
With cameras everywhere.
24 hours a day.
For millions of years.
3.
It’s Not Worth It, Given the Distances
The universe is enormous in a way that can’t really be visualized in terms of earth travel.
You can say that alpha centauri is 25 trillion miles away, or about 40 trillion kilometers,
but it’s hard to visualize just how far that is.
If you shrink the scales down and make earth the size of a grain of sand, that star is
still several thousand miles away.
That’s still extremely close in terms of the rest of the galaxy, so needless to say
the distances involved for interstellar travel at sublight speeds are daunting and limiting.
This works the same whether you are an exploration craft or an alien invasion force.
The logistics of moving around the assets you need on those distance scales and the
time involved change the equations for whether you would invade and conquer a planet.
With enough distance, no planet is worth it, especially when you consider that such distances
also prevent you from anything close to real time reconnaissance until you get close by.
In other words, what you saw as a primitive civilization from the deck of your fleet flagship
1500 years before you reached your target could well have developed advanced weaponry
and technology by the time you were finally in proximity to invade.
That uncertainty would make any such expensive undertakings likely not feasible.
2.
We are Already Obviously and Flagrantly Dangerous
Sci fi often depicts us as woefully unprepared for an alien invasion once it happens, but
often the writers of that kind of sci fi have to essentially tone down or negate the weapons
we do have, most typically giving the aliens shields that can withstand nuclear weapons.
Little attention is paid to just how those shields function, and there really isn’t
much of a basis for such a strong yet invisible shield of this type in science.
But look at our weaponry in terms of sci fi.
If I were to tell you a story about an interstellar war where one side possessed weapons that
had the effect of recreating a piece of a star right next to a space ship, you would
assume that the ship would be destroyed.
But, that’s more or less what a hydrogen bomb is, an advanced nuclear fusion device
designed specifically to destroy something.
While bigger bombs can be envisioned, the fact that we have H-bombs at all, and as a
civilization achieved that technology so early means that anyone else in the galaxy probably
has them too, and that may be enough to keep otherwise hostile alien civilizations from
messing with us or anyone else.
And, there’s more reason to think this than simply blowing up the alien’s flagship.
At sub-light speeds, we’re probably going to detect a giant invasion fleet well before
it gets close.
But even if we don’t, if for some reason we don’t think we can target the aliens
with a nuke or don’t have time, we can still target ourselves with a full global thermonuclear
exchange and go out in a blaze of glory and poison the planet for the invaders.
Such a thing could be arranged very quickly on this world, minutes, on the orders of only
a handful of world leaders.
1.
Earth Itself Could Be Deadly Poisonous to Biological Aliens
The biggest improbability in sci fi regarding alien invasions is that aliens could stand
around on earth without a spacesuit.
You can’t do that anywhere in this solar system other than earth.
Same for any exoplanet we yet know of.
Stand on Mars wearing little but a tee shirt you are soon dead.
The surface of Venus is way worse.
In fact, you can’t even breathe in Earth’s own oceans without technology and fish likewise
can’t usually breathe the atmosphere.
And even if you could breathe Mars’ atmosphere, you’re still dead from the sun’s unbridled
radiation pretty quickly.
And then there is the much lower atmospheric pressure.
Point is, the universe is mostly deadly to you anywhere except your home planet and the
same is likely true for aliens.
But it gets worse.
Your own planet in the past has been hospitable to life itself, but deadly for you.
Go into the far future and it will be deadly again.
You can only exist on your home planet under natural circumstances for so long.
While it’s hard to envision intelligent life existing on anything but oxygen, there
are few chemical alternatives to run large brains, the oxygen levels of atmospheres could
vary wildly, along with the other gases present.
In short, Earth probably wouldn’t have the right mix for an alien to breathe, which would
make this planet virtually useless for conquest and colonization.
So that’s ten reasons why real world extraterrestrials would not invade earth.
So you can sleep well tonight knowing that tomorrow you probably won’t wake up to your
new alien overlords.
Unfortunately, there is another side to this coin, so expect a future video detailing ten
reasons aliens might invade.
Thanks for listening!
I am futurist and science fiction author John Michael Godier and if you would like to help
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