"Alien motiviations" Topic

So why would aliens invade anyway? If a species had the ability to travel between solar systems what would they need from other worlds?

Here are some things they would not need
Water-there is a huge amount of ice in the Universe, so if a culture could travel through interstellar space it can probably melt ice as needed.

So the goofy "aliens are invading for water really makes no sense, or for most other resources either, energy is more easily available in deep space than on a planetary surface.

I think the reasons for alien expansion are all cultural.

I can races that want to "Uplift" other species, whether those other species want to be uplifted or not

A race that doesn't want any competition might be compelled to ensure its security by dealing with any life bearing worlds nearby. Of course nearby becomes infinite as borders get pushed out.

Also a race that wants to expand may need worlds upon which to live. Like the aliens in Independence Day the new owners would want to "clear out the roaches" before they move in

Like you said, perhaps liveable worlds like ours are rare. Another species which grew up in similar conditions would rather take our world than go through the many years of terraforming a rock.

Perhaps they need organic materials for food or fuel? Or even for medical reasons?

Food, water, rare minerals, slaves, pets, etc., etc..

Could be a philosophical imperative to conquer every culture at least once.

While things may be available in space, it is much more fun to make the nasty humans provide them for you.

or perhaps well aged, well fed humans are tastier, so gamers watch out.

They need women?

"Mars Needs Women"

The only reasons I can think of would be cultural; and I think the chances are if they still practise organised aggression by the time they can cross interstellar space, they won't be around long enough to bother anyone.

Population growth out of control. Safer to raise children on a planet than in space.

I'm going with "they want our women". We have the most beautiful women in the universe, after all (I mean, we even have the Miss Universe contest, and we haven't even developed interstellar drive yet!). Also, there were all of those paperback book covers from my youth showing strange, obviously non-human, aliens carrying off beautiful human women.

I especially liked Shyalaman's movie Signs (2002) for absurdity. Aliens invade the Earth -- but it turns out what water, which covers 70% of the Earth's surface and is present as vapor throughout most of the atmosphere, actually destroys their bodies. What idiots were on their Invasion Target Selection Committee? Why didn't they just invade Mars?

I think invading to take over a habitable world is perhaps plausible. It's probably easier and faster than terraforming.

Taking resources is also plausible, but of course not resources commonly found in space, like water. Maybe they need gold (traditional) or lanthanum (because I'm a Traveller player). In that case, total invasion would not be necessary. They would just take over South Africa and Sweden, respectively.

As the OP and Grignotage say, a likely reason is habitable real-estate. But far from invading, they would probably want to eradicate all Terran lifeforms, in order to seed the planet with their own biology. An easy way would be to deploy a large foil blanket in solar orbit at .9 AU from Sol, blocking all solar radiation from Earth like an ongoing total eclipse. Station a few interceptor ships nearby to destroy Earth's desperate rocket salvos, wait for a few years until the planet is a nice iceball devoid of life, then remove the orbital blanket, let the planet thaw out, and voila – a new world ready for colonization, with no casualties and very little fuss.

Living space isn't really a realistic reason. If you have the tech to travel interstellar distances you're going to simply find that building or converting livable space is much more cost effective than trying to conquer it.

Resources are possible but it would need to be some sort of weird and so far undiscovered unobtanium; stuff like metals and water can be mined out of any variety of rocks that no one is going to fight you for.

Cultural reasons ('we conquer because we must') seems like the most plausible.

-Will

"Variable Star is a 2006 novel written by Spider Robinson based on the surviving seven pages of an eight-page 1955 novel outline by the late Robert A. Heinlein."

link

There are several interesting concepts in this book, ideas that Heinlein expressed about the fragile world we live upon, and how we are inexorably destroying it as well as those natural (X-Rays from a Black Hole bathing Earth and extinguishing all life) and unnatural dangers from other worlds.

There was also either a TV special or book where I read how the best way that aliens might wipe out life without sacrificing the planet, the most dangerous being large projectiles dropped from orbit next to the coasts of our continents that would effectively flush a majority of humanity out of existence and leave the rest to enslave or dine upon. The interests in our world deal with biologically close aliens repopulating, or rare elements they may plunder, or exotic delicacies to dine upon as noted previously.

There are many scenarios, but I have to agree that we've only been looking at our corner of the Galaxy for the last 50 years, while life may have already come and gone on other planets, or just begun to sharpen stone axes, the probability of any extraterrestrials being interested or even noticing Earth is pretty astronomical no matter how much noise or probes we may send out…

I know, I'm kind of a pessimist.

Tasty humans.

No doubt a delicacy in some cultures, including some here on Earth.

Who knows, we may even get to find out, if we survive next week's asteroid pass.

Pre-emptive strike.

They heard about how we exploded the Samsung Galaxy and figure we are too dangerous to leave alive.

Perhaps they seeded the place or pushed us along, and we've finally gotten the smog and carbon dioxide there they want it?

Or they think Earth contains some resource it really doesn't? (Fountain of youth? Seven cities of Cibola?)

There are motivations in my home town I never have figured out, and worse for the country at large. What sort of people travel hundreds of miles to watch two teams of mercenary athletes fight it out. not being friends or relatives of any of the players, and no money on the game? (IS Superbowl Sunday this weekend? Not that I would find World Cup Soccer an improvement.)

Maybe whichever clan loses the big game has to go invade another planet.

Chlorophyll, where else in this system can you find it?

The predator aliens just liked to hunt sentient species. Good a reason I suppose.

something hard to manufacture with their technology….

endocrine, protein chains, stem cells, neurons..human hair?

maybe something not even human, we're just in the way of them collecting all the guano or ambergris they can steal?

"To Serve Man"

ufoseries.com/faq.html

This'll do…

Cultural if it includes 'let's conquer/destroy/stir up the ants nest' just because we can….or prevent the uncivilised humans from expanding into space…..or using human slave soldiers because they are adaptable and compliant….

While I'm aware of the concept of any raw materials in the hands of a sufficiently advanced race can be engineered into all you can need, I'm not entirely sold that planets are superfluous.

I'll even give that the materials in the asteroid and Kuiper belts could create habitats for uncounted lifeforms, but I'm just not convinced that a biosphere isn't so incredibly efficient, and already in place or requiring comparatively small 'terra-forming' (our opponents wouldn't be Terran), that one can discount their desirability for some time.

Mind you, I also know 'what is needed' is damn parochial. A major problem with exobiology is how much it depends on biology.

Doug

They've been watching us try to destroy ourselves and are worried that we might be reaching a technology point where we will be a danger to the rest of the galaxy.

For the raw materials? Could we be those raw materials i.e. batteries as in the ill fated Skyline movie.?

If that was the case I hear you ask why couldn't they just grow life forms to "feed" off. But after all they are Aliens and why should they think like us. If they are a locust like society why not just move from life bearing planets to planet living on the edge of extinction each journey?

We can't assume the intelligence equals wisdom.

maybe they are just A holes

Have you read about the Dark Forest cosmology theory?

I don't want to spell it out here as it involves spoilers for Cixin Liu's excellent Three Body trilogy, but it could certainly provide some answers.

Maybe they are just bored & went out in search for some 'fun'.

Perhaps they just dislike vermin.

Kinda like a galactic version of kids kicking over an ant hill to see what happens.

"So the goofy "aliens are invading for water really makes no sense, or for most other resources either, energy is more easily available in deep space than on a planetary surface."

Often said, and there is water in space such as in our Oort cloud. But it isn't liquid. and unless it is, it's not that useful except as reaction mass. And are you really going to go to all the trouble to construct giant containers to melt it when there's plenty of liquid water in toward the center of the system?

Perhaps economics also factor into it: There's a delightful story by Edmund Hamilton about a planet that picks it's best and brightest, sends them to Earth, has them trained in operating complex machinery to manufacture water from hydrogen and oxygen* and brings them back. Most don't want to return, because at least on Earth, it doesn't rain all the time like it does on the colony world.
Yes, it rains there. Rain. But just gathering the rainwater would be counterproductive and a waste of the investment in training and purchasing the machinery.

Perhaps also, invading aliens just never heard of Nietzsche any of the "Action is pointless due to logic" philosophers :)

* Yes, that *should* be easy especially as the colony gets a lot of electricity from hydroelectric power. . . . But value needs to be added for economic reasons.

I've given careful consideration to all the theories posted.

I like cosmicbank's the best.

"Maybe they are just a- holes". 👽

We are in the wrong place in the wrong time. Blank Frontier Zone agreed among galactic main empires is now in dispute, so we are in the very middle of the opening movements of a new Galactic Great War.

So, the reason is purely strategical. No other interest for them.

Maybe with all their science and technology, some things are just better off being done with slaves labor force.

In myths/theory the Anunoki use mankind as a slave force, maybe they will come back and do it again!

Gees what a bunch of "A" holes!

I'm still going to vote for living space, for one simple reason: a habitable planet is a LOT of living space, for any civilization short of one capable of making Dyson Spheres, and you don't need to physically build it.

Secondary reasons would be cultural.

Plus, I suspect that half the reason Earth hasn't been officially visited by aliens is because they're afraid we will take over.

Often said, and there is water in space such as in our Oort cloud. But it isn't liquid. and unless it is, it's not that useful except as reaction mass. And are you really going to go to all the trouble to construct giant containers to melt it when there's plenty of liquid water in toward the center of the system?

If the planet is inhabited by militant locals with nuclear weapons? Yea, I'd take the iceballs. Solar energy to melt them is cheap in space. Plus all that liquid water is down there in a super-unhelpful gravity well. :)

The problem with living space is still that you're assuming the aliens would even find Earth comfortable, or inhabitable period. Based on what we've seen of exo-planets, this strikes me as looking increasingly unlikely.

-Will

The problem with living space is still that you're assuming the aliens would even find Earth comfortable,

Merely assuming any aliens that would want to invade would find changing to suit easier than a lot of other planets.

If they don't, we shouldn't see them, except… see below.

In the solar system there are, what, maybe five or six that might work?

And not sure the outer moons as candidates are that good.

However, a methane-based life form might fight to the death for Titan.

I love the concept of a battle for the solar system where the combatants discover they prefer totally different real estate. Followed by best buddies conquering the galaxy.

Doug

Indeed. Start with why do we want to find habitable words and go from there.

Dan

What about they invade just because they can. Sure they can get lot of water and power in space. But what if they just want to bring that world to it's knees because they need a cheap and disposable work force. So they land and take your world just because they can.

The problem with living space is still that you're assuming the aliens would even find Earth comfortable,

Merely assuming any aliens that would want to invade would find changing to suit easier than a lot of other planets.

Anyone willing to invade (as opposed to rocking us from orbit) would find our rock comfortable enough. If the aliens don't want Earth, there's no reason to visit Earth at all. They could be doing all sorts of stuff in the Belt as we speak, and there's not a thing we humans could do about it.

Maybe they're generally good about minding the "Do not feed the humans" signs posted along the far rim of the Oort cloud.

Because humans were still living in caves when they launched their colony ships and now that they have finally arrived after a *very long* journey turning back isn't an option.

I liked that last one!

Anyone willing to invade (as opposed to rocking us from orbit) would find our rock comfortable enough. If the aliens don't want Earth, there's no reason to visit Earth at all. They could be doing all sorts of stuff in the Belt as we speak, and there's not a thing we humans could do about it.

Well that's my point; if you really need the planet for some odd reason and not the people on it then dropping rocks on it is much, much more likely. I mean for the human biosphere to be useful you're going to need something that likes roughly an oxygen/nitrogen atmosphere at 1 atmosphere of pressure, 1 G of gravity, is DNA based, uses similar amino acid chains, etc etc. Any one of those doesn't match and Earth is not a very appealing colonization target as is; it would just as easy to smoke the locals from orbit and tweak the planet from there. From what we've seen of exo-planets so far that close a match would basically be an extremely long shot.

I think motivation would basically have to boil down to 'we need the humans alive' for some reason. That's why cultural motives make more sense to me; you could probably invent a plausible reason why the Aliens won't/can't/don't just wipe out the humans but some other reason to invade.

Because humans were still living in caves when they launched their colony ships and now that they have finally arrived after a *very long* journey turning back isn't an option.

Isn't there a Harry Turtledove series that deals with this? But I agree it's a neat concept, since even if the Aliens are way, way higher tech than the Humans they didn't come prepared for an all-out war, so there is a better possibility the fight will be even enough to be interesting.

-Will

Yes. Harry Turtledove's World War series is based on the concept of an alien species that is long lived and develops very slowly sending a probe to earth during the early Middle Ages. Based on that information and assuming humans would develop at a pace similar to their own they decide earth is a good candidate for colonization and they send out a handful of ships that arrive at the height of World War II.

The aliens are stunned and horrified at the astonishing pace of human development. Their military technology isn't much more advanced than today's modern technology and the aliens' colonization force only contains a small military force that was intended to provide security for the scientists, engineers and farmers that make up the bulk of the colony force. They aren't prepared for a real fight, but they can't turn back and have no choice but to invade.

There are a couple of other neat twists too. A big one is that their concept of warfare differs from ours. Their idea of war is similar to how dogs establish the pecking order in a pack. When the aliens decide to invade they fully expect that we will become happily submissive and accept our new place in the pack once the aliens demonstrate their dominance. They are again mystified and horrified when the humans keep fighting back and resisting even more fiercely after the aliens launch a few devastating attacks.

The books are great.

Yes, that's right, it's all coming back to me; the Aliens had military tech that was like early 21st century (versus every else's 1940s tech) and had nuclear weapons but of course did want to use them since there was a full fledged colony fleet on the way with no easy way home (no FTL, right?). Neat scenario.

-Will