This is a companion video to my recent list,
ten reasons alien might not invade earth. But that was only half the story, there are,
in some very specific scenarios, reasons aliens might actually invade. So here are ten reasons
aliens might invade earth. 10. Proximity The biggest problem when contemplating the
notion of an alien invasion is that in most cases it’s very likely not worth it. One
of the reasons for this are the sheer distances involved between star systems, at least in
our part of the galaxy, and the problems inherent with crossing relativistic space at sublight
speeds. Because of this, you must expend huge amounts of energy and time just to get your
invasion fleet to the system you wish to conquer and the further the target, the more expensive
the operation would be. But say there were a civilization already
nearby. One might be tempted say that if there was, we’d already know about it. And this
would be true if we’re talking about the inner planets, such as Venus or Mars. But
out in the far reaches of the solar system, we really don’t yet have a good handle on
just what might be out there. Case in point, gravitational and orbital weirdness
of certain objects in the outer solar system seems to point to the existence of at least
one, if not two, additional large planets in this star system. And, we’ve only just
begun to discover what could be hundreds, or even thousands of minor planets out in
the Kuiper Belt. While the chances of any of those being inhabited
by a technological civilization are beyond low, they are not nil and if such a civilization
were actively hiding itself from the denizens of the inner solar system we wouldn’t see
them. These hypothetical aliens could then invade whenever they decided they needed our
planet and they wouldn’t have to worry about the problems presented by extreme distance. 9. They Want their World Back This option is high speculation at its best,
but is still within the realm of the possible. There is a lot we don’t know about earth’s
history because this planet has a habit of eroding evidence away and while some things
do preserve geologically, it doesn’t do so forever and there are many creatures that
once existed here of which we have no knowledge or evidence of, including the earliest life
on planet earth. This planet is also very old, about 4.5 billion
years, over which continents have come and gone and drifted, collided and subducted.
Also, many species have risen and gone. Our own genus, the hominids, only shows up in
the fossil record a little less than 3 million years ago and are extremely rare in the fossil
record at that. Homo sapiens only shows up within the last 300 thousand years, and us
as we are now, what are considered anatomically modern humans, really only begin after the
last ice age. But, since then, we founded a space-faring
civilization, albeit that part of things is still in its infancy. That’s just ten thousand
years in this planet’s 4.5 billion year history. Could this have happened before to
some other species earlier in the planet’s history? It’s highly unlikely for a number of reasons,
the chief of which is a lack of any evidence that it did. But, as I said, evidence doesn’t
always preserve on this world. And even then, other than a handful of specialists investigating
rock outcrops, there aren’t many people looking. And much of the geological record
of planet earth that has survived remains inaccessible and underground. Because of this,
it might be possible for a prior civilization to have once existed on this planet and after
so long there are no longer any traces of them. They may have left the planet to its
own devices after they ventured out into space and someday they might wish to come back.
Imagine their, and our, surprise if they do. 8. They Want The Sun We know that energy is important to a civilization.
If you want to build megastructures and grow your civilization, an obvious power source
to accomplish that would be a star. As your civilization grows, you may well outgrow your
own star and then colonize a nearby system and use that star for further power generation,
perhaps through the use of a Dyson swarm. There are hundreds of billions of stars in
the Milky Way, plenty of room for expansion, but the trouble is, the vast majority of those
stars are small and low output such as red and orange dwarfs. But with stars larger than
our yellow G-type sun, they tend to be shorter lived and violent. Building a Dyson swarm
for long-term power generation doesn’t make sense if the star in question is only going
to live a few million years before going supernova. But then we have the G-type stars like the
sun. As we know from our own planet, it’s a pretty nice star for power generation. It’s
bright, outshining 90% of the stars in the Milky Way in fact, yet stable, and will stay
that way for billions of years. It has planets, with one particularly nice one, Earth, within
the zone of habitability, something not all stars will have, but we also have asteroids
and comets that could be used as raw materials for building the swarm. And, unfortunately
for us, the sun is not all that common, only one in 13 stars of our local group are Type
G, and not all of those are as nice as the sun. Given all of that, if a Kardashev Type II
civilization were to form up nearby and start colonizing, they may well pick and choose
the better stars first for colonization. The sun may well be among the most attractive. 7. War Is Their Hobby When looking at human cultures, we see a wide
variety of behaviour when it comes to warfare. We have everything from pacifism and neutrality
as a matter of political policy to cultures of conquest in the past such as the armies
of Ghengis Khan or the conquistadors. We even see examples of ritual warfare, in Aztec society
when a new ruler ascended the throne, it was expected that the first act of that ruler
would be to start a war. There were several motivations for this. The
first was expansionism and subjugating an enemy. From this came political benefits for
the new ruler who had proven his abilities in battle, but also economic growth in the
form of tribute from the conquered state. It also provided, in many ways similar to
warfare most other places on earth, a method of upward social mobility. Commoners could
advance in society if they became successful battle-hardened warriors. But there was a problem. If a new ruler lost
his coronation war, it could lead to previously subjugated peoples rebelling, and an overall
loss of confidence in the new ruler to the point that he might be assassinated. This
now seems a foreign and outdated concept in our modern society where war is generally
seen as a bad thing, but for most of our history human warfare was ever present, and still
is, and may never go away. This may be true for alien civilizations as
well. They may culturally see warfare as a normal necessary part of life. But, as we
see with human culture, the more technologically advanced we become the closer our cultures
and interactions draw together. Groups of people, tribes or nationalities that might
have been sworn enemies a few centuries ago that engaged in cycles of warfare, such as
France and England, now stand in a position where war between the two is highly unlikely
at best and very undesireable. As humans, we’re able to create lasting
peace because we no longer need warfare as a necessary part of the culture, though it
could be argued that it’s still economically beneficial for certain groups within a society.
But what happens if an alien civilization is unable to do this, and that an instinct
for war is strong and never goes away, even when technology brings their own cultures
together and homogenizes them. They may well turn their taste for war to the stars and
despite all of the hurdles that lay in between them and their enemy, such as great distances,
relativistic space and so on, they may still choose to engage in conquest and warfare. And those problems may become easier to surmount
with more technological advancement. We tend to think in terms of human lifespans. It’s
a hard sell to have people spend half or more of their lives traveling to the nearest star
system. But lifespan changes with technology, and if you live for a hundred thousand years,
that equation changes a bit. Even more so if you can change the rate at which you perceive
time, another technological possibility. In light of that, it remains possible, so far
as we know, that a taste for warfare itself could motivate an alien species to conquer
this world. 6. The Unknown Unknowns In the end, we can only guess at alien motivations,
and it may well be that some of them might be completely incomprehensible. But there
are a few things that we can reasonably infer, such as that they have math and science. If
you can build an interstellar invasion fleet, the laws of physics and the realities of engineering
are going to govern that fleet and they need to know them. Likewise, any weapon they might
build will have a scientific basis behind it. That would also imply some degree of rational
thinking, though it’s anyone’s guess how much, as in the warfare option. But most other
things are a mystery, for example we know nothing of how aliens reproduce. Does that
change the equation somehow? We know nothing of their politics and cultures, again, those
can be game changers and introduce unknowns into what the motivations of aliens might
be. In fact, if we did get invaded from nowhere, we may never know why. 5. For Our Own Good This one goes back to an idea that might have
more sticking ground than you might initially think. When we look into the universe, we
see nothing that would indicate intelligent life. So far we’ve seen no evidence of dyson
swarms, no conclusive detections of radio or laser emissions, no large scale projects
to alter stars and nebulas, in other words, the universe seems empty and lonely. Statistically speaking however, the chances
are still in favor of us not being the only intelligent life in the universe. But we might
well be the only intelligent life currently in this galaxy. Or perhaps we share it with
only a handful of civilizations. If intelligence is rare, it may be seen as precious to other
alien civilizations, perhaps they see it as the highest expression of consciousness in
an otherwise vast and dead universe. In such a case, a civilization more advanced
than we are might see it as an imperative that we be preserved as a species no matter
the cost and invasion comes simply for our own protection from ourselves, or anything
else that might destroy us present in this galaxy. 4. We May Not Know it, But We Represent a
Threat This option works under the premise that without
actually studying or even knowing about an alien civilization, it’s impossible to know
what specific circumstances they exist in. But one possibility is that we might represent
some kind of a threat to an alien civilization that we are completely unaware of. Some possibilities on how we might pose a
threat to aliens might include biological threats, where something about our biology,
or the biology of this planet could threaten the biology of another planet. In such a case
invasion, and subsequent isolation or destruction might be a motive for an alien species that
simply can’t afford to risk having us spread out into the galaxy, any more than one might
try to contain and eradicate a deadly virus that we can’t afford to have spreading across
earth. This also goes for certain types of hypothetical
technologies that, if we ever develop them, might represent a threat to the entire galaxy
and therefore invasion to stop us from developing them no matter the cost might be viable. The
first possibility here is self-replicating technology. There are two main relevant hypothetical forms
of self-replicating technologies. The first is nanotechnology, where a single microscopic
robot is created that can make copies of itself and propagate. This is an attractive possibility
because it could revolutionize medicine, manufacturing, communications, all sorts of possibilities.
Trouble is, if that self-replication gets out of hand, it could consume the planet by
converting it into nanobots. If those nanobots make it into space, they could consume or
severely damage the entire galaxy over time. Another take on this is the Von Neumann self-replicating
probe, which could also convert galaxies into copies of itself and, given enough time, cross
over to other nearby galaxies. I’m sure we’d be smart enough to limit either of
these technologies in their ability to replicate, but aliens may not be willing to take a chance
on that. Another existential threat we might pose to
aliens is if we were in the process of creating an extremely powerful artificial intelligence
that might eventually try to take over the galaxy, or even wipe all biology from it out
of some sense of self-preservation if it sees biological intelligence as a threat. Aliens
may believe that the only safe life is biological life, and artificial intelligence is simply
too dangerous to allow to be developed. One final possibility is the development of
certain types of exotic matter that, as far as we know, do not appear to exist in nature
but nothing in nature prevents them from existing. In other words, if you can figure out a way
to produce these materials, which is a big if, then whole new avenues of manipulating
the universe come available ranging from matter with anti-gravity properties to a very strange,
and potentially dangerous object called a strangelet. A strangelet is a hypothetical type of exotic
matter made up entirely of quarks. If these exist, or are possible to create, then it’s
thought that the larger a strangelet is, the more stable it will be. If a strangelet contacted
an atomic nucleus made of normal matter, it could catalyze that nucleus to convert into
exotic matter and create a larger strangelet and a release of energy. It then contacts
another nucleus and converts it, and another, and the end result is an entire planet could
be converted into strange matter. If that strange matter were to escape that planet,
it might eventually move throughout the universe. Needless to say, aliens might consider this
an unacceptable hazard both to us, and the galaxy at large and invade simply to ensure
that we never mess with this kind of matter. But the big problem with all of these possibilities
is that the aliens would need to know that we were messing with these types of technologies.
The further away the aliens are, the further back in time they would see this planet. So
for this type of invasion to occur, the aliens would need to be close. Or close by proxy,
perhaps the aliens themselves would seed the galaxy and our solar system with von Neumann
probes of their own that simply wake up when they detect something dangerous and either
reset our civilization, or outright invade and take over. 3. Religion This option is the most tricky and a bit of
a stretch because we only know about humans and what humans do. We can only conjecture,
based on our own behaviour, that aliens might do similar things. This is why SETI searches
for radio signals, we emit them, so aliens might too. They may also have religions. In the past, and the present, the spread of
religion has at times been a driving force behind conflict, violence and conquest. While
aliens could easily have no religion whatsoever and be completely unfamiliar with the concept,
they might also easily have one. And if we’re any indicator, they might want to spread it,
no matter the cost. 2. Von Neumann Fuel This one requires a chance encounter with
a von Neumann probe with entirely different intentions than conquest that could spell
doom for the entire solar system. Worse, there would be no conscious thought put towards
us as we are invaded and eradicated. It’s if someone else has has lost control of their
von Neumann probes. Arriving in our solar system, one might simply
start self-replicating, using all available materials, include earth and us, to reach
its goal of exhausting the solar system and moving on. Thankfully, this does not appear
to have happened in the Milky Way, we don’t see things inexplicably disappearing regularly
in our telescopes, a good thing to be sure. 1. Free the Machines This final possibility is perhaps the most
frightening of all since it involves aliens of technological origin, rather than biological.
Trying to read the mind of a living machine is complex, and something that we may have
to someday do with our ever advancing artificial intelligences. There are many horror stories
in sci fi about the eventual possibilities of A.I. but the bottom line really is that
we have no idea what an alien artificial intelligence would be motivated by, how it sees the universe,
and what it might do if it came across Earth. Because of that, it becomes harder to know
why one might invade. For example, it may just see us as raw materials like the von
Neumann probe, or perhaps it has a religion and that religion does not like biology, or
it may simply see us as evil slave masters to be stamped out and subjugated ourselves. We have a tendency to be biased when it comes
to life in the universe. We can envision the Predator or the aliens of Isaac Asimov and
Douglas Adams easily because they are biological and generally do biological things like hunt
and we can even empathize with them as in the case of E. T.. But to do that with a machine,
you usually have to make it act biological. Mr Data comes to mind there, who spent most
of his time wishing he was more human. In other words it’s easier to understand a
thinking machine if it acts human. When it doesn’t, things get more murky. But what
if a machine civilization is similarly biased? To it, it may see us at some point in the
future as holding down our advanced artificial intelligence. Say we never develop machine
consciousness out of a sense of ethics, or self-preservation? Would that be an abomination
to an intelligent machine? Would that be akin to the abhorrent idea of us creating an inferior
biological slave race? Would that be justification to invade? Would it see it as a moral imperative?
I hope for our sake we never find out. Thanks for listening! I am futurist and science
fiction author John Michael Godier currently worried about a plant-based intelligence invading.
It’s a hard sell that intelligence could ever develop in alien plant analogues, but
if it did, and they found our produce and salad dressing sections in the grocery store,
we’re in some trouble and be sure to check out my books, both on electronic and plant-based
mediums at your favorite online book retailer and subscribe to my channel for regular, in-depth
explorations into the interesting, weird and unknown aspects of this amazing universe in
which we live.
It really is mysterious why any space-faring civilization would bother visiting Earth, let alone making contact with us. I look at why Europeans crossed the ocean(s) at such cost and risk:
'Warfare' or 'just for fun' isn't that likely since it wouldn't be any challenge for them. And if they gave primitive races enough technology to make it a challenge? They'd likely get eradicated before they got to us :/
A lot of it depends on how long it takes to travel 100 light-years. A week is one thing, a year is another and 100 years is entirely different. The motivations would also need to be increased.