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molten_dragon
2013-10-02, 07:59 PM
I've started to do some early planning for a future campaign I want to run. It's going to be an alien invasion campaign. Something like Falling Skies, though not quite so apocalyptic. The players will be playing a team of scouts/spies/saboteurs/gurillas/etc. who get sent behind enemy lines to support the war effort to take back the US east coast. It's going to be run using the FATE core rules.

The thing is though, I'm a big science nerd, and I love hard sci-fi, so I want it to be as realistic as possible. I don't want aliens who came here for our water, or ones who are allergic to water but came here anyway, or ones that have computer systems that can interface with a macbook. I want them to have a realistic reason for coming to earth, and realistic technology. And I want a war that the humans have a chance at winning.

So here's what I've come up with so far.

The aliens came from very close by in a galactic sense (My initial thoughts are an undiscovered planet orbiting Delta Pavonis or 61 Virginis). Biologically they're quite similar to us, they breathe oxygen, they live in similar temperature conditions, they're probably going to be either aquatic or amphibious. Some sort of cataclysmic event happened on their homeworld. They weren't able to stop it, but they were able to build an ark ship and try to save their species.

They came to earth because it was the only inhabitable planet they thought they could reach. They came in a generation ship powered by a bussard ramjet. They didn't find out until they were on the way here that earth was already inhabited. Once they did, they decided (in a close decision, there will probably be a 'rebel' faction that doesn't support attacking humanity) that with the future of their species at stake, they couldn't afford to try and negotiate with us and have us say no, and that they probably couldn't win a military conflict unless they struck first from surprise. They built a refueling/repair station somewhere in the solar system (I'm leaning towards the kuiper belt) and studied us for awhile, making plans and learning what they could about us.

There will be relatively few of the aliens (maybe a hundred thousand?), but their military will be highly automated (lots of unmanned combat vehicles) to help increase their numbers quite a bit.

So here's what I'm having trouble coming up with so far.

What kind of cataclysmic event would drive a society that was capable of building a bussard ramjet to flee their home planet?

What kind of weapons technology would be expected from a society with that level of technology?

If you were a member of such a society, how would you prosecute a war against earth, with the eventual goal of being able to live on the planet (or at least a good-sized chunk of it)?

Any other help or advice would be much appreciated.

Deffers
2013-10-02, 08:23 PM
The problem I see is that if you're making fabrication stations out in the Kuiper Belt, you can already stomp us. I mean, basically, you can just send out very big, dense rods and drop them on our capital cities and information supercenters. If you can build giant naval ships, you can probably just take whatever stealth technology you were going to use and save yourself the metal by just dropping a solid block of scrap on targets of opportunity. Were I the alien commander in charge of the U.S., for example I'd hit Google, then I'd hit NORAD, then I'd hit D.C., all from orbit. I'd extend this pattern, too; civilian telecomm and military targets in near-tandem, followed by actual political centers. We'd be talking a span of minutes, here, too. As far as civilians would know, it was a conventional nuclear attack. Anybody in the know would probably be going "wait, WTF just happened" and would suspect other human countries. I'd advise my fellow-generals to see how this would play out and see if whatever Dead Man's Hand system they've got going in Russia will do its thing when a nation's telecommunications spine has just been broken and it's looking for targets. I mean, of course I'm going to leave the U.S. nuclear capable. They don't have missiles that can point to where I'm hiding, and even if they could I'd still be able to detect them and have plenty of time to bat them out of the sky. The only people they'd be able to hit are the people they'd immediately suspect, which would be their future allies.

You might be wondering why I'm prioritizing the civilians over the military. It's simple. The civilian populace poses the biggest threat because they're the ones that there are a lot of. They're not in uniform. They're not in ANYTHING. They're spread out everywhere. You don't want to be fighting them. The LAST thing I want to do is just let these people know I'm invading them.

Assuming I don't have the technology to clean up massive nuclear fallout, I'd let a few bombs drop in, yunno, capital cities, and then Rod From God the military bases and nuclear weapons of the rest of the world. Come forth as friendly fellow sapients, and appear to be benevolent. I mean, we just stopped a nuclear war, after all. Incidentally, could we room with you guys? Our generation ship has been searching for a home and, wouldn't you know it, we detected signs of life and thought you could help us out. Lucky we came in time.

From there, allow mass radiation to spread out the human population and reduce urban centers. Live out a few more generations in radiation-shielded arcologies while the stuff dissipates. Have time to research, in depth, the biological makeup of Earth. See if you can integrate or improve your position.

And then, the reaping can begin. Or, I mean, if cooler minds prevail, then obviously you'd just figure out a way to integrate humanity into a wonderful bi-species situation with you as the technological and economical superior. Your people can rest easy at night, the local populace gets to not completely die off, and even if people find out the deception, the trouble communicating means you can wipe them out at your leisure and nobody will be the wiser.

You'll notice that the plans fall apart if the word gets out and suddenly you have full-scale civilian insurrection on your hands. That's where the PCs come in. :smallamused:

As to what sorts of weapons they could have? All kinds. Lasers for aerospace supremacy, use of microwaves as painful stun shields, all the stuff we've got on the experimental scale but suddenly mass-produced, reliable, and efficient. Ultrasonic pulses that detonate missiles going at vehicular targets, necessitating an up-close approach... that sort of deal.

Zavoniki
2013-10-02, 08:34 PM
If you don't know about it already I would suggest looking at: http://www.projectrho.com/public_html/rocket/index.php

It has a very good section on why/how to have a war in space. Its more oriented towards ship v ship combat, but could still be helpful.

To answer your questions:

1: I think anything here needs to threaten the aliens home solar system. Maybe the stars going to go nova is all I can think of but they key point here is that if you are capable of building an arcship I feel like you should have infrastructure and support around the solar system. Simply threatening the home system isn't enough.

2. Atomic rocket has a lot of information about this(though again oriented toward space combat) but its basically for planetary small arms combat the only thing I can see is Railgun's and Missile's. For space they should also have Lasers but those have issues when it comes to things like Atmosphere and need a lot of power. Also robots but you already mentioned that part.

3. This is where a problem comes in. The way I would do it is precision kinetic bombardment. Send small chunks of asteroid that are too small to cause permanent harm but can do serious damage until the humans are dead/surrender. But turning that too a roleplaying idea I see two ways to go:

A: Ignore it. The arcship is damaged/they are running out of supplies and don't have time to bombard the planet and/or don't have the resources.

B: What I would do, give the humans a little bit of an assist in that they get some kind of interceptor project built that can shoot down the projectiles before they hit. The aliens then need to land infantry forces to take out this platforms. The problem then is why can't the platforms shoot down the alien shuttles and why can't they use that technology on their projectiles.

Basically it's hard to find a scenario where there is a balance. Either the aliens have the resources of a solar system against a single planet and win or the humans get the resources of Earth against a single massive ship and win. It's also hard to imagine any kind of ground combat occurring at all.

Toy Killer
2013-10-02, 08:34 PM
Step 1: Destroy oil rigs
step 2: ???
Step 3: Profit.

Deffers
2013-10-02, 08:42 PM
Petroleum engineer here! That wouldn't work for numerous reasons. First one, it's too fast to rebuild one or just drill a new hole. Second; a completed well is a tiny, tiny thing. Contrary to popular belief, all that rigging doesn't stay up. They're just there while the drilling happens. After that you rig down and move out and let the completions people do their job.

Beyond that, the U.S. strategic oil reserves are hidden inside a salt dome. I'd be impressed by what you'd need to do to the ground to get that to start leaking. It'd be easier to just take the area and fry anything that came near, but this'd still be incredibly resource intensive since you'd be holding a key area within enemy territory while continually trying to destroy all wells.

Honestly, if you want to halt oil production, hit the refineries, because they're not as easy to rebuild and you're going to have problems of scale on small fractional distillation units.

At least, my two cents here.

EDIT: The problems of scale mostly have to do with stocking a platoon's worth of jeeps.

Mr Beer
2013-10-02, 08:53 PM
As mentioned above, the main problem with realistic alien invasions is that if they have star travel tech and we have current tech, they can use orbital bombardment at will. I think the advantage would be like us invading mediaeval societies, given an unassailable base of operations and bomber squadrons with an infinite fuel reserve in that base.

As the aliens, I would load up with smallish rock or iron balls, enough for explosions up to about a megaton and take out all the cities over a certain size. Not sure what it takes to create a nuclear winter, if that looks like becoming a problem, dial down to 10 KT and use more rocks. Also take out all the nuclear weapons and military targets. Watch civilisation collapse, walk in.

The actual land invasion and holding what they take would be achieved by heavy satellite coverage with back-up orbital weapons systems mainly consisting of aerodynamic metal rods with a small computer guidance system and steerable fins. Cheap, you could have millions of them up there and with GPS/laser guidance and plentiful high-tech satellites, it would be easy to destroy resistance.

What humans would be able to do what would be guerilla hit and runs. But bear in mind the organised governments/military has gone and it will take less than a year for 80% of the world population to starve to death, probably more in Western nations and less in Africa.

Gnoman
2013-10-02, 08:54 PM
If they're relying on drones without a human-level AI, the aliens LOSE, hands-down. Unmanned combat vehicles have to be remote-controlled to be able to perfom basic friend-foe discrimination, let alone any sort of fancy combat maneuvering. All you would have to do is pump the battlefield with electronic interference (the EMP from a nuke would do it, as would large amounts of white-noise jamming from aircraft), and all those drones are completely useless, as their control signals can't get through. Then you send a couple of piloted aircraft to Paveway their base and go home.

Edit: Any large scale orbital bombardment would inflict massive damage on the biosphere, essentially a nuclear winter. Orbital/Nuclear bombardment is only useful if you want to sterilize a planet, not occupy it.

Deffers
2013-10-02, 09:06 PM
Yeah, that's why I'm advocating hitting crucial targets, letting politics do the rest, and doing surgical strikes on the remaining nuclear missiles and silos. Sure, you've got one or two smoking craters, but you've mostly got an intact earth!

Mr Beer
2013-10-02, 09:06 PM
Edit: Any large scale orbital bombardment would inflict massive damage on the biosphere, essentially a nuclear winter. Orbital/Nuclear bombardment is only useful if you want to sterilize a planet, not occupy it.

Fine, dial the explosion size down. Say they decide they want North America first. Instead of 100 cities with 15KT each, hit 10,000 infrastructure and military targets with 100 ton equivalent yields.

warty goblin
2013-10-02, 09:14 PM
If their goal is the utter destruction of humanity, and they want a habitable planet, orbital bombardment isn't probably the way to go. Instead why not unleash super-virulent plagues aimed at major crops? The real beauty of it is that the countries with the best militaries are also the most dependent on industrial agriculture, which do not have a large amount of genetic diversity in their primary crops. After 80% of the industrialized world has starved to death, it should be a lot easier to re-zone a continent or two for prime alien real estate.

If you don't want to go all bioware, there's always planetary scale terrorisim. Park in high orbit and let it be known that until such time as the entirety of, say, Australia, is evacuated and handed over, one randomly selected Earth city an hour will be vaporized. With the exceptions of cities in Australia; there's no sense blowing craters in the backyard. Just so that nobody thinks they're kidding around, vaporize someplace relatively small to get the point across.

Should holding major population centers hostage not go over so well politically, you could always alpha strike the living daylights out of the military and political base. Every aircraft carrier or other major surface vessel should be blown to smithereens. Every GPS satellite gets ground up for scrap metal. Every capital of a major power is simultaneously and completely atomized. Every town with a military base gets blown up as soon as practical, in descending order of size. Once there isn't a single facility capable of launching a fighter jet left in the world, deploy the ground drones.



As for what sort of units they would deploy, how about some mix of the following:

1: Infantry drones. Say about human sized. Give them something nasty in the realm of weaponry, and lots of explosives. After all civilian casualties probably aren't such an issue. These self-coordinate with each other at the small group level, and can have specialist configurations, e.g. mortar-bot, missile-bot, machinegun-bot, etc.

2: Coordinator drone. Basically a big server that decides what information gets shunted from one group of combat units to each other. They don't run the other drones, which are autonomous and capable of limited self-organization, they simply coordinate and direct. Blowing one up doesn't shut down all the drones it commands, it just removes their higher order directives and information sharing.

3: Tactical air drones. Take the best fighter jet you can think of, make it stealthy as all getout, capable of higher G maneuvers than any human pilot, and linked directly to the infantry drones through the coordinators. A group of infantry with support from an air unit will thus know where every relevant enemy the air unit can see is, and the air unit knows everything it needs to about the ground situation. Can be loaded with whatever missiles, guns, etc you want.

4: Heavy land drone. Basically armored vehicles. Also capable of auto-coordination with local infantry units. Also comes in whatever configurations are convenient; direct assault, transport, artillery, etc.

And whatever else strikes your fancy. But if they're using drones, they should be extremely well coordinated.

Traab
2013-10-02, 09:20 PM
Fine, dial the explosion size down. Say they decide they want North America first. Instead of 100 cities with 15KT each, hit 10,000 infrastructure and military targets with 100 ton equivalent yields.

Just avoid the nuke portion. Crater everything larger than a town including any military bases. As has been said before, any space faring race of aliens is likely going to have a massive tech advantage. Someone mentioned signal blocking the drones and such. That might work, but only if they use signal tech that we can recognize and effect. And considering he mentioned wanting to avoid the whole interface with a mac book deal, it may not be the kind of thing he wants to see happen.

As a question, how much damage would obliterating every satellite in space do as an opening salvo? How badly would it disrupt communications? Halt our ability to gain intel?

Ravens_cry
2013-10-02, 09:26 PM
The trouble with a resource war is that all that crap is already out there in the form of asteroids and comets. Not only is there no pesky natives to beat down, the gravity wells are much, much shallower. So, if they are already in space, getting them that way is magnitudes easier that way than going all xenocidal.

Gnoman
2013-10-02, 09:32 PM
Just avoid the nuke portion. Crater everything larger than a town including any military bases. As has been said before, any space faring race of aliens is likely going to have a massive tech advantage. Someone mentioned signal blocking the drones and such. That might work, but only if they use signal tech that we can recognize and effect. And considering he mentioned wanting to avoid the whole interface with a mac book deal, it may not be the kind of thing he wants to see happen.


If they use any form of radio signal. ANY form, pumping white noise on that frequency or setting off a nuke will disable the control link. You don't need to interface with the tech at all, any more than you need to speak Japanese to completely disrupt conversation in a Tokyo street with a microphone, huge speakers and a massively amplifier. They could use laser links, except those are line-of-sight only, so the controller would have to be very close to the drone, which negates the main point of using drones in the first place.

Mr Beer
2013-10-02, 09:44 PM
The trouble with a resource war is that all that crap is already out there in the form of asteroids and comets. Not only is there no pesky natives to beat down, the gravity wells are much, much shallower. So, if they are already in space, getting them that way is magnitudes easier that way than going all xenocidal.

That's why the war has to be about land or something else, although of course while there's an argument it would be easier to terraform asteroids, at least lebensraum is plausible.

This nonsense about aliens turning up for water or gold (see History channel for plenty of this) is just ridiculous.

Deffers
2013-10-02, 09:54 PM
The theory I've heard is that if an alien species were fighting a war we could even conceivably win instead of hitting us from afar, it would be because they are interested in us, not in our resources. Lebensraum is a feeble argument 'cos of meteors and comets, as was mentioned-- I'd think that's right. That means that for some reason they'd want to do something with the population. What, exactly?

Ravens_cry
2013-10-02, 09:59 PM
That's why the war has to be about land or something else, although of course while there's an argument it would be easier to terraform asteroids, at least lebensraum is plausible.

This nonsense about aliens turning up for water or gold (see History channel for plenty of this) is just ridiculous.
If they can live on a bussard ramjet propelled craft for however many generations it would take to get to our solar system, they have off world life down to a science. If they need the living space, they can just make more from the aforementioned asteroids and comets. Honestly, it's no more plausible than gold, water, or any other bulk commodity for that matter.
An idea I had is they move in and start mining space based resources just as humanity advances to the point where it becomes feasible to do this ourselves.
Now, I think, you got something. Their need to survive verses them taking the resources we need to become a fully spacefaring species.
Now you got some drama and conflict.

Deffers
2013-10-02, 10:07 PM
Maybe that's it. Maybe the reason they're not wiping us out is because we could serve an economically expedient purpose otherwise and they're trying to elbow out just-booming resource competition?

That would make any war with us a highly messy affair meant to subjugate instead of destroy, and would result in a lot of messy opinions across the entirety of the population-- banned subjects on their star-forums, to put it another way. :smallamused:

warty goblin
2013-10-02, 10:25 PM
The trouble with a resource war is that all that crap is already out there in the form of asteroids and comets. Not only is there no pesky natives to beat down, the gravity wells are much, much shallower. So, if they are already in space, getting them that way is magnitudes easier that way than going all xenocidal.

There's where you can live, where you live because you have no other choice, and where you want to live. These are not necessarily the same things. Eating nothing but plants is massively easier than raising meat; people still eat hamburgers.

Deffers
2013-10-02, 10:34 PM
Yes, but would you kill a living being that had demonstrable thoughts and feelings just like you, at the same depth as you, for a quarter-pounder? Would you be able to pull the trigger day after day knowing that it was only dumb luck that you got the gun first and penned these cows in first, and if things changed maybe he'd be the one pulling the trigger for his Baconator?

'Cos if you could, and you could get your entire species to agree with you, that would be a truly alien race.

Ravens_cry
2013-10-02, 10:52 PM
There's where you can live, where you live because you have no other choice, and where you want to live. These are not necessarily the same things. Eating nothing but plants is massively easier than raising meat; people still eat hamburgers.
After several generations aboard ship, that would likely be the new normal. Besides, unless Earth is absurdly like their homeworld, it really wouldn't be all that homey. Imagine if you got transported back in time before flowering plants. That would probably be more familiar than Earth compared to their home planet.
They would be better off making O'Neill cylinders (http://en.wikipedia.org/wiki/O%27Neill_cylinder) configured to their home biome.
And if Earth, against all odds, somehow was similar enough to their old world that got them homesick and could sustain them, they might actually be in danger from an unprepared immune system.

Mr Beer
2013-10-02, 11:18 PM
Maybe they like large spaces and O'Neill cylinders don't cut it? I know we've said they're used to their arkship, but maybe they want more. Maybe they are hardwired for open spaces and a generation or two isn't enough to kill that desire.

Ravens_cry
2013-10-02, 11:36 PM
Maybe they like large spaces and O'Neill cylinders don't cut it? I know we've said they're used to their arkship, but maybe they want more. Maybe they are hardwired for open spaces and a generation or two isn't enough to kill that desire.
Then build another design. Or, heck, terraform Venus or Mars.

warty goblin
2013-10-02, 11:39 PM
Yes, but would you kill a living being that had demonstrable thoughts and feelings just like you, at the same depth as you, for a quarter-pounder? Would you be able to pull the trigger day after day knowing that it was only dumb luck that you got the gun first and penned these cows in first, and if things changed maybe he'd be the one pulling the trigger for his Baconator?

'Cos if you could, and you could get your entire species to agree with you, that would be a truly alien race.

Me? No. But I'm not some betentacled beasty from deep space, looking for a nice place to settle down and lay a mass of squirming eggs.

Consider for example, something with the life cycle of a parasitic wasp. I'd figure moral qualms recognizable to humans would be pretty absent in a species whose first act is to eat something alive from the inside out. In the compound eyes of a beast like that, humans wouldn't be so much fellow sapients as convenient protein sacks conveniently lacking hard exoskeletons.

Prepare to be ovi-posited.



Besides which, if one is doing the whole alien invasion thing, having fairly scumbag aliens is kinda a given. That the only intelligent species we know of combines sapience with some levels of compassion hardly implies the two must go hand in hand.


After several generations aboard ship, that would likely be the new normal. Besides, unless Earth is absurdly like their homeworld, it really wouldn't be all that homey. Imagine if you got transported back in time before flowering plants. That would probably be more familiar than Earth compared to their home planet.
They would be better off making O'Neill cylinders (http://en.wikipedia.org/wiki/O%27Neill_cylinder) configured to their home biome.
And if Earth, against all odds, somehow was similar enough to their old world that got them homesick and could sustain them, they might actually be in danger from an unprepared immune system.
Earth minus flowering plants would still be vastly preferable to spending the rest of my life in an overgrown tin can.

There's also a bit of a reach between 'can survive in space' and 'can build O'Neill cylinder.' Particularly if there's only ~100,000 of the things, it hardly seems unreasonable to conclude that engineering on that scale is rather out of reach. Unless for some reason that was the entire population of their original planet, that suggests that whatever they did to get this far was essentially as much as they could manage. It's rather like saying the existence of a cruise ship is clear proof we can build a floating city to house the population of Lagos any old time.



Then build another design. Or, heck, terraform Venus or Mars.
OK, there's out there, and then there's the completely absurd, aka terraforming Mars. Terraforming Venus is quite a few steps beyond that.

Besides which, the object of the exercise is to have aliens invade. Not every narrative needs to degenerate into a 'everything we ever need forever is in space' fantasy.

Deffers
2013-10-02, 11:58 PM
Consider for example, something with the life cycle of a parasitic wasp. I'd figure moral qualms recognizable to humans would be pretty absent in a species whose first act is to eat something alive from the inside out. In the compound eyes of a beast like that, humans wouldn't be so much fellow sapients as convenient protein sacks conveniently lacking hard exoskeletons.
Prepare to be ovi-posited.


Now, see, I'd agree with you, but there's some aliens who don't agree with smashing the puny humans within their factions. We must ask ourselves; why? Would a sapient parasitic wasp be unable to, for example, appreciate a good poem? Would they find literally no worth in another being that can sing, that can emote, that can battle with self-righteous fury for its very survival? If not, then, well, why are there wasp monsters sympathetic to us? If so, then the cow question comes into play. Maybe you'd feel OK laying your eggs inside one of our many cows, very few of which can compose sonnets. And Daisy's meter is always off these days. Girl's getting up in years. Would they have a taboo against laying eggs in your fellow wasp-alien? Can that empathy be used?

For invaders to be interesting, they have to be at least somewhat human sometimes. Otherwise, why NOT obliterate them down to the last? Because we're the better species? Well, the better species would make sure that something which can't be reasoned with that would target its young would be swiftly dealt with. See: disease, predation, etc.

Vamphyr
2013-10-03, 12:13 AM
If they're making the effort to come here specifically, I would have them show up to harvest our genetic material. They could be using it for food, research, weapons, biotech, anything really.

Also, aliens are going to have morals and thought processes that are completely different from ours. At times they will perform actions that make no logical sense to a human, but that's okay, it only has to make sense in the context of their species.

If a race s as advanced as what we re discussing here, it would be hard to find anything to truly threaten them as far as extinction level events go. A few things I can think of off the top of my head, and possibly to be used together:

Black hole - a star collapses, forms a super massive black hole, and begins devouring their solar system entirely, not much left for them to do but flee. If it was only a black hole, however, why would their only be 100k of them remaining?

Some form of invasive predator - let's face it, space is huge and there are bound to be some things we can't even imagine going down. You could throw in an invasive species (like the flood from halo, or the alien from Slither) who's sole form of reproduction or survival involves consuming all the organic matter on a planet and then launching a piece of itself into space to find another world to devour.

Under this I would also include: a race who's fundamental building blocks were of an irradiated material, thus their very presence on any world like ours is toxic.

Cthulhu-esque horrors - they used to worship it as a god until it consumed 99.8% of their population and only 100 thousand of them could flee. Now it wants the rest of its promised children to rest eternally inside itself.

Or, another race of advanced aliens who specialize in eradicating species and consuming their resources. There are people and governments that earn a lot of money by invading their neighbors, killing them, and taking their things. If they have a vast society that needs to b supported, it would be plausible they wouldn't care about killing "lesser species" for the sake of their own success and survival.

Now we would be stuck dealing with a race who is acting in terror and self preservation trying to take over our world, while the real monsters follow close behind....

Deophaun
2013-10-03, 12:15 AM
Orbital/Nuclear bombardment is only useful if you want to sterilize a planet, not occupy it.
Which, being that these are aliens and so have an alien biology, is probably exactly what they would want to do. Would hate to get killed off by the common cold. They probably intercepted that movie on the way here.

Ravens_cry
2013-10-03, 12:20 AM
Earth minus flowering plants would still be vastly preferable to spending the rest of my life in an overgrown tin can.

There's also a bit of a reach between 'can survive in space' and 'can build O'Neill cylinder.' Particularly if there's only ~100,000 of the things, it hardly seems unreasonable to conclude that engineering on that scale is rather out of reach. Unless for some reason that was the entire population of their original planet, that suggests that whatever they did to get this far was essentially as much as they could manage. It's rather like saying the existence of a cruise ship is clear proof we can build a floating city to house the population of Lagos any old time.

An O'Neill cylender is actually quite feasible if we were willing to invest the time and money, and we are at the bottom of a gravity well unlike that of any rocky planet in our solar system.
Besides, using organic based systems for life support may very well be the best system for a long term project like a generation ship. After all, it's what Earth does.
OK, there's out there, and then there's the completely absurd, aka terraforming Mars. Terraforming Venus is quite a few steps beyond that.

Besides which, the object of the exercise is to have aliens invade. Not every narrative needs to degenerate into a 'everything we ever need forever is in space' fantasy.
It is hardly a fantasy when the Delta-V for reaching asteroids and comets is positively minuscule compared to landing on a rocky planet such as our own.
My point is the OP wanted a realistic invasion plan, and a resource war for Earth is just not realistic. They might as well be after Earth's women.
Xenoforming is probably a bit out there. Or maybe not. If they can be lucky enough that Earth is almost home to them, they can be lucky enough that Venus or Mars are similar enough to wherever they came from that a few tweaks and it's just like home.
On a side note, Venus's upper atmosphere is among the most Earth-like places in the solar system. You can't breathe the air, but the air pressure and temperature are surprisingly terrestrial, all that gas protects from most space radiation, and the gravity is close.
Not really on topic, but good to know in case we have leave Earth. Oh, and air is a lifting gas, so you can basically have flying cities.

Erik Vale
2013-10-03, 01:52 AM
If they're aquatic, I see very little problem with orbital bombardment, as long as they don't go so far as to cause the oceans to freeze over, they're fine. No need to deploy robots, which as said, will be laughed at once EM interference starts being set up unless they are self controlled with smartish animal intelligence.

If I had good enough bio-engineering, I would create a few human specific and crop specific plagues to unleash assuming I needed the land.

However, if they're just amphibious and need land for a large amount of time, I could imagine bombardment of the world, the aliens choosing a section to more thoroughly cleanse, and then settle taking over the rest of the world slower. Doing it this way would allow for a game, as you could play survivors protecting EM interference devices while trying to kill the aliens, where each alien kill is a big thing, but should your devices go down, fit hits the shan.

The Grue
2013-10-03, 02:41 AM
If their goal is the utter destruction of humanity, and they want a habitable planet, orbital bombardment isn't probably the way to go. Instead why not unleash super-virulent plagues aimed at major crops? The real beauty of it is that the countries with the best militaries are also the most dependent on industrial agriculture, which do not have a large amount of genetic diversity in their primary crops. After 80% of the industrialized world has starved to death, it should be a lot easier to re-zone a continent or two for prime alien real estate.

This strategy has another advantage: assuming the invaders can obfuscate their involvement in said plague, they get to ride in and play Saviours to the starving, crippled human race. "We'll use our advanced space-science to help you engineer crops that are resistant to your super-plague," they can say, "and we'd be glad to teach you what we know about materials science and high-energy physics, maybe even offer some insights into your medical technology. All we ask in return is a place to settle, because we had to flee our homeworld and we don't have the resources to find another suitable planet."

The survivors of Earth would be happy to offer up some prime real estate to these guys, don't you think? Now instead of having to fend off the world's primitive inhabitants, they have access to a cooperative, grateful indiginous population.

ShadowFireLance
2013-10-03, 03:33 AM
Something I've noticed with a lot of movies/books/etc is that either;
A) The Local Military gets steamrolled.
B) They win so hard it isn't even funny.
C) They fail at large but one group beats the entire alien invasion.

Try to get the balance in the middle.

Just a 2Cence.

erikun
2013-10-03, 05:23 AM
The biggest reason I can think of to avoid orbital bombardment (that is, landing planetside instead) is due to the danger of setting of nuclear bombs. Remember that the aliens want to populate Earth, not wait for some nuclear fallout to go away before populating Earth. As such, it would be much more practical to take control of any nuclear centers, especially those with missiles, to ensure that humanity doesn't start bombarding them/each other/the environment with them.

It also gives a good reason for the aliens to take over the United States, and most other important countries. Most of these places have a nuclear arsenal. It would also explain why they can understand the local language and communicate - they'd want to be sure they can capture these important areas when first making contact.

As for points of interest, this motivation would mean that the aliens would be making great effort to dismantle nuclear weapons and getting rid of them - either by putting them into reactors, shipping them to their "base" outside orbit, or possibly by just tossing the material/waste into the sun. This wouldn't necessarily be common knowledge, and the PCs might have some fun conflicts and/or diplomatic possibilities when they find out. It could also build some good environment for the setting, as not only have the aliens taken over governments but they are regularly launching spacecraft to their orbital stations.

molten_dragon
2013-10-03, 06:08 AM
The problem I see is that if you're making fabrication stations out in the Kuiper Belt, you can already stomp us. I mean, basically, you can just send out very big, dense rods and drop them on our capital cities and information supercenters.

Yeah, they likely could simply wipe us out, but I don't intend for them to do that. I don't really even intend for them to be all that hostile towards humanity, simply desperate for their species to survive. Basically, their intention will be to strike first so that they can eventually negotiate with us from a position of strength.

And dropping rocks will definitely be a part of their initial invasion plan. I intend to have a large one drop in the Atlantic to basically wipe away most civilization on the east coast, and that's where they'll start settling. The rest of the country will be hit with targeted strikes to military bases, power plants, dams, and other targets which will disrupt our ability to fight back effectively without killing us en-masse.

molten_dragon
2013-10-03, 06:16 AM
If you don't know about it already I would suggest looking at: http://www.projectrho.com/public_html/rocket/index.php

It has a very good section on why/how to have a war in space. Its more oriented towards ship v ship combat, but could still be helpful.

I'll definitely check that out, I wasn't aware of it before.


1: I think anything here needs to threaten the aliens home solar system. Maybe the stars going to go nova is all I can think of but they key point here is that if you are capable of building an arcship I feel like you should have infrastructure and support around the solar system. Simply threatening the home system isn't enough.

Yeah, I was kind of thinking this too. However, none of the logical choices I've found for star systems they could be from are ones that could have a sun that's destabilizing without us knowing about it. I'm kind of leaning towards something they did to themselves. Some type of planetary engineering gone wrong or something.


3. This is where a problem comes in. The way I would do it is precision kinetic bombardment. Send small chunks of asteroid that are too small to cause permanent harm but can do serious damage until the humans are dead/surrender. But turning that too a roleplaying idea I see two ways to go:

A: Ignore it. The arcship is damaged/they are running out of supplies and don't have time to bombard the planet and/or don't have the resources.

B: What I would do, give the humans a little bit of an assist in that they get some kind of interceptor project built that can shoot down the projectiles before they hit. The aliens then need to land infantry forces to take out this platforms. The problem then is why can't the platforms shoot down the alien shuttles and why can't they use that technology on their projectiles.

Basically it's hard to find a scenario where there is a balance. Either the aliens have the resources of a solar system against a single planet and win or the humans get the resources of Earth against a single massive ship and win. It's also hard to imagine any kind of ground combat occurring at all.

This is kind of what I'm having trouble with too. I think that's why I'm basically going to go with psychological/societal reasons for why they aren't just wiping us out and landing once the dust settles.

What I'm thinking of is that the decision to attack us from surprise at all was a very controversial one, a significant minority of their population didn't support the idea. Which is why the decision was made to wage a limited war and negotiate from a position of strength, rather than trying to wipe us out. Basically those in charge worried that the minority who opposed an attack would go from disagreement to outright rebellion if they tried to wipe us out.

molten_dragon
2013-10-03, 06:17 AM
Petroleum engineer here! That wouldn't work for numerous reasons. First one, it's too fast to rebuild one or just drill a new hole. Second; a completed well is a tiny, tiny thing. Contrary to popular belief, all that rigging doesn't stay up. They're just there while the drilling happens. After that you rig down and move out and let the completions people do their job.

Beyond that, the U.S. strategic oil reserves are hidden inside a salt dome. I'd be impressed by what you'd need to do to the ground to get that to start leaking. It'd be easier to just take the area and fry anything that came near, but this'd still be incredibly resource intensive since you'd be holding a key area within enemy territory while continually trying to destroy all wells.

Honestly, if you want to halt oil production, hit the refineries, because they're not as easy to rebuild and you're going to have problems of scale on small fractional distillation units.

At least, my two cents here.

EDIT: The problems of scale mostly have to do with stocking a platoon's worth of jeeps.

Petroleum distilleries will definitely be on my list of targets for precision bombing.

molten_dragon
2013-10-03, 06:23 AM
If they're relying on drones without a human-level AI, the aliens LOSE, hands-down. Unmanned combat vehicles have to be remote-controlled to be able to perfom basic friend-foe discrimination, let alone any sort of fancy combat maneuvering. All you would have to do is pump the battlefield with electronic interference (the EMP from a nuke would do it, as would large amounts of white-noise jamming from aircraft), and all those drones are completely useless, as their control signals can't get through. Then you send a couple of piloted aircraft to Paveway their base and go home.

I'm not so sure I agree with that. With our level of technology, sure. But in a hundred years, I'm betting we'll have drones with some level of autonomy. Especially if identifying friend vs. foe is made easier by the fact that the foe is a completely different species.

And I don't think it's too farfetched that they would have communications technology we couldn't jam. Could WWII era technology jam our communications? I kinda doubt it.

And besides, who says they're going to let a nuke or an electronic warfare plane, or a bomber get anywhere near an area where they're conducting military operations?

Rods from god my friend.

molten_dragon
2013-10-03, 06:28 AM
There's where you can live, where you live because you have no other choice, and where you want to live. These are not necessarily the same things. Eating nothing but plants is massively easier than raising meat; people still eat hamburgers.

This is kind of what I'm thinking of. While they might be able to survive indefinitely in space, they aren't prepared to risk the future of their species on a maybe. Habitable planets are a lot safer.

Lorsa
2013-10-03, 06:52 AM
What kind of cataclysmic event would drive a society that was capable of building a bussard ramjet to flee their home planet?

A total flip in the magnetic field of the planet? Their version of skynet? Maybe the sun was dying?


What kind of weapons technology would be expected from a society with that level of technology?

Quite similar to our own I imagine, just more computerization. Laser (or the derivatives thereof) makes for a fairly bad weapon all things considered. Highly directed plasma could theoretically work I suppose but ballistic weapons are very simple and work very well.


If you were a member of such a society, how would you prosecute a war against earth, with the eventual goal of being able to live on the planet (or at least a good-sized chunk of it)?

Biological warfare. The most efficient way to wipe out another species or civilization is to use an infectious agent that you are immune to. Not to mention it would leave most of the world untouched.


Any other help or advice would be much appreciated.

Good luck? :smallsmile:

Randel
2013-10-03, 07:14 AM
What kind of cataclysmic event would drive a society that was capable of building a bussard ramjet to flee their home planet?

What about Strangelets (http://en.wikipedia.org/wiki/Strangelet)? Some of their scientists were working on some kind of warp drive or whatever and it accidentally created strangelets which convert all matter they contact into more strangelets (basically like the gray goo scenario except instead of nanobots which could potentially be reprogrammed, you've got a mess of incredibly dangerous exotic particles that can't safely interact with normal matter).

So the accident spread strangelet particles around the solar system and many of their planets, asteroids, and perhaps even their star have been infected and being converted into strange matter. They left because pretty much all the resources in their solar system was being destroyed by the strange matter. Fortunately, the particles break down fast enough that the effect can't leave their star system.

molten_dragon
2013-10-03, 07:42 AM
Quite similar to our own I imagine, just more computerization. Laser (or the derivatives thereof) makes for a fairly bad weapon all things considered. Highly directed plasma could theoretically work I suppose but ballistic weapons are very simple and work very well.

I think I'm going to stick with projectile weapons weapons for most of their offensive capability. I'm thinking railguns and something like an advanced version of metalstorm should be well within their technological capability. And missiles of course. Very smart missiles.

I was actually thinking of them having pretty advanced laser technology, but used defensively, rather than offensively. Picture something like the MTHEL laser that can shoot down incoming artillery shells but small enough and precise enough to shoot bullets out of the air.

molten_dragon
2013-10-03, 07:47 AM
What about Strangelets (http://en.wikipedia.org/wiki/Strangelet)? Some of their scientists were working on some kind of warp drive or whatever and it accidentally created strangelets which convert all matter they contact into more strangelets (basically like the gray goo scenario except instead of nanobots which could potentially be reprogrammed, you've got a mess of incredibly dangerous exotic particles that can't safely interact with normal matter).

So the accident spread strangelet particles around the solar system and many of their planets, asteroids, and perhaps even their star have been infected and being converted into strange matter. They left because pretty much all the resources in their solar system was being destroyed by the strange matter. Fortunately, the particles break down fast enough that the effect can't leave their star system.

That's an interesting idea. I'll have to do some more research on it.

I also thought of maybe something related to research into an alcubierre drive. Maybe they screwed something up and ruined their planet/solar system that way.

Or maybe a wandering brown dwarf star passes through their solar system wrecking things, similar to H.G. Wells short story "The Star".

molten_dragon
2013-10-03, 07:49 AM
An idea I had is they move in and start mining space based resources just as humanity advances to the point where it becomes feasible to do this ourselves.
Now, I think, you got something. Their need to survive verses them taking the resources we need to become a fully spacefaring species.
Now you got some drama and conflict.

The problem with this is that it would require advancing our technology much closer to theirs, which would make a single ark ship much less of a threat.

Plus if all they wanted was space based resources, why bother coming to a system with an inhabitable planet at all?

I need them to have a reason to want/need our planet, not just the rest of our solar system.

I don't think it's that unrealistic. There's a big difference between building something that can allow you to live in space for a few generations and building something that can allow you to live in space forever.

molten_dragon
2013-10-03, 08:06 AM
Something I've noticed with a lot of movies/books/etc is that either;
A) The Local Military gets steamrolled.
B) They win so hard it isn't even funny.
C) They fail at large but one group beats the entire alien invasion.

Try to get the balance in the middle.

Just a 2Cence.

This is basically what I'm trying to go for.

I also want to point out that I realize parts of this scenario are unrealistic. Hell, just the fact that intelligent alien life exists on a planet very similar to ours at such a close level of technological development within a couple dozen light years is unbelievably unlikely. However, I don't need everything to be completely realistic. I want it to be as realistic as possible given the constraints of the game I want to run (an alien invasion).

The aliens aren't going to sterilize earth with rocks or nukes or a virus, because I want people around for the players to play.

And they aren't going to just avoid the earth and live in space forever because the whole point of the game is an alien invasion.

SassyQuatch
2013-10-03, 08:07 AM
The invaders are actually an army of acolytes on a crusade. Their race is the only race brought to life by the Creator, thus humanity are the progeny of the Corrupter.

They are willing to destroy almost all of humanity, but on the trip a sect has gained prominence. They believe that convertion of the Corrupter's spawn could lead to them turning upon the Corrupter himself, leaving only the Creator's followers behind.

Because of this sect a few select areas have been left to survive. Humanity still resists, but they must not go too far lest their resistance lead to the aliens abandoning their efforts at conversion and destroying the humans who remain.

As an added problem there could be a number of humans who have converted. The aliens are less concerned with human violence against humans, so the PCs have a bit more leniency in their actions than if they were to target the aliens themselves. It would also add more drama, either with the Resistance infiltrating the Convert army or with themselves being infiltrated or sold out.

Because why not? Alien crusaders are awesome.

SethoMarkus
2013-10-03, 08:46 AM
I would suggest reversing the roles somewhat, as the only way that I can see an alien invasion resulting in anything but complete eradication of the human race is by humanity being the aggressor.

Rather than the alien race seeking to attack Earth with a preemptive assault on the infrastructures, with a minority/rebel faction wishing for peaceful negotiations, swap them. Make it so that the leaders/majority population of the alien race wants peaceful contact; they want to try to negotiate terms with the human race by explaining their situation. A minority faction of the aliens would rather bombard Earth from space, however, and secretly enact such a plan behind the majority's back.

This way, a diplomatic truce can be called near the end of the conflict rather than one side eradicating the other. Neither side is a "bad guy", but both sides definitely have evil, malicious agents that are prejudiced against the opposing factions. Both sides are acting out of fear and self-preservation, believing their only chance for survival is in defeating the other side.

The PCs could start off as secret military Spec Ops agents, sent in to start striking at the aliens' weaknesses after the initial (rebel) alien strike against humanity. While behind enemy lines, they begin to see that the aliens are just as confused, thinking that the humans struck first and instigated the conflict. Slowly, they can realize that the human armies were manipulated into fighting (humans really don't like being used or told what to do), simultaneously making peaceful contact with non-rebel aliens that really just want the conflict to end. They can begin helping these friendly aliens spread word and uncover the conspiracy of the original terrorist/rebel aliens that started the conflict.

There would be 5 major factions, excluding the PCs:

Humans wanting to eradicate the aliens out of prejudice.

Humans wanting to strike back at the attacking alien force.

Aliens wanting to eradicate the humans out of prejudice.

Aliens wanting to strike back at the attacking human force.

Aliens wanting both sides to negotiate peace.

(Of course, there would be humans wanting peace as well, but that should largely be handled by the PCs.)

Kaveman26
2013-10-03, 09:06 AM
Who says their arrival on earth has to be voluntary? Put them at a technological level sufficiently above our own that you are comfortable with, but sufficiently below the whole "we win by default" level. Instead of an arkship, they could be a scout vessel that was thrown via anomaly into an area near earth and they view the earth as a lifeboat. They need the majority of our resources and enough time to develop them in order to return to their system. They are small enough to not be overwhelming but large enough in number to take control and put us on our heels.

molten_dragon
2013-10-03, 09:26 AM
Who says their arrival on earth has to be voluntary? Put them at a technological level sufficiently above our own that you are comfortable with, but sufficiently below the whole "we win by default" level. Instead of an arkship, they could be a scout vessel that was thrown via anomaly into an area near earth and they view the earth as a lifeboat. They need the majority of our resources and enough time to develop them in order to return to their system. They are small enough to not be overwhelming but large enough in number to take control and put us on our heels.

That seems like it would be a very difficult balance to pull off. Why would a scouting vessel have more than a few dozen aliens on it? Thousands certainly seems extreme. So either they are so far outnumbered that it doesn't matter what they do, or their technology is so advanced that we have no hope. It's hard to come up with any kind of logical middle ground there. Plus you run into issues with having a stable breeding population.

warty goblin
2013-10-03, 10:02 AM
Now, see, I'd agree with you, but there's some aliens who don't agree with smashing the puny humans within their factions. We must ask ourselves; why? Would a sapient parasitic wasp be unable to, for example, appreciate a good poem? Would they find literally no worth in another being that can sing, that can emote, that can battle with self-righteous fury for its very survival? If not, then, well, why are there wasp monsters sympathetic to us? If so, then the cow question comes into play. Maybe you'd feel OK laying your eggs inside one of our many cows, very few of which can compose sonnets. And Daisy's meter is always off these days. Girl's getting up in years. Would they have a taboo against laying eggs in your fellow wasp-alien? Can that empathy be used?

A chicken sings (for certain values of the term), emotes, and will fight like the dickens for its life if it perceives something as a threat. Hell, when it comes raw courage, your average barnyard rooster makes us look a species of pathetic cowards; they'll happily throw themselves at a person tens of times their mass with murder in their tiny little eyes to protect their territory and harem. How many people do you know who will attack an elephant using their fingernails? I know all this about chickens, I find a lot of it admirable even. I still eat 'em for supper, and find their embryos make a really fabulous breakfast.

Other people come down differently, and object to eating chickens on moral grounds. Other people still happily eat their BBQ chicken omlets, then go back to planning how best to kill other people. You've even got a few people who don't eat meat, but still go around killing people.

My point being that you could reasonably have divisions in the aliens about proper action, even they don't care particularly about whether we are intelligent or not.


For invaders to be interesting, they have to be at least somewhat human sometimes. Otherwise, why NOT obliterate them down to the last? Because we're the better species? Well, the better species would make sure that something which can't be reasoned with that would target its young would be swiftly dealt with. See: disease, predation, etc.
I'm not sure I'd call those so much the marks of a better species, so much as the marks of us. There's nothing particularly immoral about getting eaten by wolves, unless you make the a priori assumption that a person is worth more than a wolf. Which we do, but we're hardly objective in the matter. Bug eyed tentacle beasts from beyond the Oort cloud may rule that one quite differently.

And if destroying threats to offspring is the mark of a better species, holy hell do we have it coming from the livestock of the world.


This strategy has another advantage: assuming the invaders can obfuscate their involvement in said plague, they get to ride in and play Saviours to the starving, crippled human race. "We'll use our advanced space-science to help you engineer crops that are resistant to your super-plague," they can say, "and we'd be glad to teach you what we know about materials science and high-energy physics, maybe even offer some insights into your medical technology. All we ask in return is a place to settle, because we had to flee our homeworld and we don't have the resources to find another suitable planet."

The survivors of Earth would be happy to offer up some prime real estate to these guys, don't you think? Now instead of having to fend off the world's primitive inhabitants, they have access to a cooperative, grateful indiginous population.

I think the real plot benefit is that it seamlessly integrates all manner of alien abduction/sighting stories. Of course the aliens are landing in the middle of nowhere, making crop circles and experimenting on cows, instead of stopping by downtown NYC and saying hi. They don't want to announce their presence, they need crop samples and a good understanding of bovine biology.


This is basically what I'm trying to go for.

I also want to point out that I realize parts of this scenario are unrealistic. Hell, just the fact that intelligent alien life exists on a planet very similar to ours at such a close level of technological development within a couple dozen light years is unbelievably unlikely. However, I don't need everything to be completely realistic. I want it to be as realistic as possible given the constraints of the game I want to run (an alien invasion).

The aliens aren't going to sterilize earth with rocks or nukes or a virus, because I want people around for the players to play.

And they aren't going to just avoid the earth and live in space forever because the whole point of the game is an alien invasion.
I so appreciate it when people understand the word 'fiction' in science fiction.

Diamondeye
2013-10-03, 10:47 AM
If you want there to be significant "behind-the-lines play in a ground invasion scenario, you need to find a good way to avoid the "bombard from orbit until submission" thing.

This isn't actually that hard to do, as "rods from God" isn't the insta-win that people seem to think it is.

The aliens are aboard a colony ship, not a warship. When they arrive, they would need to localize nuclear weapons sites (for every major power) and attack the before the humans realize what is happening, and launch everything at them. There's a principle here - use them, or lose them.

Now, ICBMs/SLBMs can reach low orbit altitudes, but aren't intended to attack targets there; that's not what they're designed for.

Therefore, lets say NASA/ the International Space Station/ other nation's space agencies detect this incoming spacecraft through whatever means, and hasty measures are taken to adapt missiles like this, as well as various ASAT/ABM systems around the world (Russian systems around Moscow, the GBI system in Alaska, SM-3/AEGIS/whatever anyone else has) are undertaken.

There's also SSBNs at sea, harder to localize and attack.

So, let's say that as soon as the Aliens show up and fling their first rods, Earth governments start salvoing anything that might possible hit them, and most nuclear missiles are either fired or destroyed early in the conflict. Since the missiles are not really designed for orbital targets, most don't do well, but enough get through the relative lack of point defense on the colony ship to seriously damage it and force a crash landing on the east coast. Still, enough of its facilities, equipment, and personnel survive to make taking North America viable.

They occupy a strip from, say, North Carolina to Boston and west to the Appalachian mountains. This means they hold DC, 2 very large cities (Philadelphia and NYC) and our largest Esat Coast naval facility (Norfolk) but the bulk of the country and our military power is in our hands. The capital relocates to Chicago, Denver, Kansas City, or Dallas, and the campaign begins.

In this way, further major nuclear attacks are avoided. We don't want to use nukes on our own soil, they don't want to contaminate resources, and other nations are.. diddling about over what to do, and whether more aliens are coming.. which might be true if they have a facility in the Kuniper belt. Those reinforcements could show up later to trouble Russia, China, or Europe, perhaps.

captpike
2013-10-03, 11:11 AM
If you want there to be significant "behind-the-lines play in a ground invasion scenario, you need to find a good way to avoid the "bombard from orbit until submission" thing.

This isn't actually that hard to do, as "rods from God" isn't the insta-win that people seem to think it is.

The aliens are aboard a colony ship, not a warship. When they arrive, they would need to localize nuclear weapons sites (for every major power) and attack the before the humans realize what is happening, and launch everything at them. There's a principle here - use them, or lose them.

Now, ICBMs/SLBMs can reach low orbit altitudes, but aren't intended to attack targets there; that's not what they're designed for.

Therefore, lets say NASA/ the International Space Station/ other nation's space agencies detect this incoming spacecraft through whatever means, and hasty measures are taken to adapt missiles like this, as well as various ASAT/ABM systems around the world (Russian systems around Moscow, the GBI system in Alaska, SM-3/AEGIS/whatever anyone else has) are undertaken.

There's also SSBNs at sea, harder to localize and attack.

So, let's say that as soon as the Aliens show up and fling their first rods, Earth governments start salvoing anything that might possible hit them, and most nuclear missiles are either fired or destroyed early in the conflict. Since the missiles are not really designed for orbital targets, most don't do well, but enough get through the relative lack of point defense on the colony ship to seriously damage it and force a crash landing on the east coast. Still, enough of its facilities, equipment, and personnel survive to make taking North America viable.

They occupy a strip from, say, North Carolina to Boston and west to the Appalachian mountains. This means they hold DC, 2 very large cities (Philadelphia and NYC) and our largest Esat Coast naval facility (Norfolk) but the bulk of the country and our military power is in our hands. The capital relocates to Chicago, Denver, Kansas City, or Dallas, and the campaign begins.

In this way, further major nuclear attacks are avoided. We don't want to use nukes on our own soil, they don't want to contaminate resources, and other nations are.. diddling about over what to do, and whether more aliens are coming.. which might be true if they have a facility in the Kuniper belt. Those reinforcements could show up later to trouble Russia, China, or Europe, perhaps.

I like this idea, it gets ride of the death from above problem, I would say that the aliens would have knocked out our satellites, and placed their own, but they might have little or no offensive abilities in orbit.

it could end up being a race to see if we can wipe them out before they construct their manufacturing facilities to make their robots or until they get reinforcements from the (now overworked) base in the kuper belt.

all of this on the backdrop of us having little to no knowledge of our enemy, even using drones and planes is hard because they use point defense lasers.

the PCs first mission could be as a team sent in for intel, and try and spot targets

Ravens_cry
2013-10-03, 01:02 PM
The problem with this is that it would require advancing our technology much closer to theirs, which would make a single ark ship much less of a threat.

Plus if all they wanted was space based resources, why bother coming to a system with an inhabitable planet at all?

I need them to have a reason to want/need our planet, not just the rest of our solar system.

I don't think it's that unrealistic. There's a big difference between building something that can allow you to live in space for a few generations and building something that can allow you to live in space forever.
The trouble is from a realism perspective is that our planet is very likely to be very different from wherever they called home. Even if they want to return to the hinterlands of their ancestors, even a small amount of resistance would mean they are better off using off planet resources to refuel, restock, repair, and then start accelerating to another system. Sure, it sucks for them, but their ancestors could take that leap into deep space, so why not them?
Why come to an inhabited system at all? Well, detecting an inhabited system is rather tricky in itself. We only recently gained the ability to detect an Earth sized planet around other systems, and we have yet to be able to detect potential biological markers like free oxygen. Depending on who you ask, our radio signals may not be detectible very far out.

GM.Casper
2013-10-03, 01:19 PM
Why does their planet need to be destroyed anyway? The ship could be a long range colonization mission, refugees from a faction that lost a war (and there's the motivation for conquering earth- for the glory of the Space-Reich).

The invasion plan would be to take out the military and higher government with orbital precision strikes, while leaving the infrastructure reasonably intact. Then they move in and establish occupational government. Collaborators are offered wealth and access to alien's medical technologies, including biological immortality.

The long term goal is to assimilate humanity into their society as a worker caste.

Logic
2013-10-03, 01:25 PM
Biological warfare. The most efficient way to wipe out another species or civilization is to use an infectious agent that you are immune to. Not to mention it would leave most of the world untouched.

The toxin of an Australian funnel web spider is nearly always fatal to humans, but mostly* harmless to other terran life forms. Regular diseases might be decent place to start, but nothing that humans would already be familiar with.

Ravens_cry
2013-10-03, 01:40 PM
Why does their planet need to be destroyed anyway? The ship could be a long range colonization mission, refugees from a faction that lost a war (and there's the motivation for conquering earth- for the glory of the Space-Reich).

The invasion plan would be to take out the military and higher government with orbital precision strikes, while leaving the infrastructure reasonably intact. Then they move in and establish occupational government. Collaborators are offered wealth and access to alien's medical technologies, including biological immortality.

The long term goal is to assimilate humanity into their society as a worker caste.
Glory alone fills no bellies, and what good are we as a worker caste? If our technology is so vastly inferior, we have little to offer them besides trinkets and cultural artifacts. These might attract an already existing post scarcity society with a eye for novelty, but not a space ark on the end of its rope.
If they want us as labor, they run into the danger of teaching us how to defeat them. It also takes a lot of energy to get to and from Earth orbit. Even if they did it by the most efficient manner possible, there is an absolute minimum (http://what-if.xkcd.com/7/).
As mentioned repeatedly, any bulk matter they need could be gotten far easier elsewhere in the solar system.

warty goblin
2013-10-03, 01:41 PM
The trouble is from a realism perspective is that our planet is very likely to be very different from wherever they called home. Even if they want to return to the hinterlands of their ancestors, even a small amount of resistance would mean they are better off using off planet resources to refuel, restock, repair, and then start accelerating to another system. Sure, it sucks for them, but their ancestors could take that leap into deep space, so why not them?


Very unlikely things happen in fiction and reality all the time.

Telok
2013-10-03, 01:43 PM
This has been done and published. Larry Niven and Jerry Pournell wrote Footfall several decades ago.

Look, your aliens have to have a way to cheaply bring mass from ground to orbit, a power source capable of running a small city for decades without refuelling, a bussard ramjet capable of reaching c-fractional in the local bubble (Sol sits near the middle of a hole where interstellar hydrogen is 1/10th normal), and the capability to engineer a fully functional ark ship. You don't want to fight them, you want to sell them prime sea-side real estate! It is a good trade to give them half of Florida for that tech.

Plus, how did they manage to hide the massive EM signature and distortions of the ramjet? Why was the Earth surprised when there was a fusion torch spraying a characteristic and easily identified spectrum of radiation across the solar system for decades? We should have been sending messages trying to buy thier fusion technology for years before they even arrived. In Footfall these questions were avoided by having the aliens arrive in the 1950's, before we knew what to look for and while everyone was distracted bythe cold war, and hiding for thirty years.

Ravens_cry
2013-10-03, 01:44 PM
Very unlikely things happen in fiction and reality all the time.
Why not have them be able to breed with humans and and want our women (or men) to repopulate their society?
Nothing against it from a literally law of physics perspective, but almost as absurd nonetheless.

molten_dragon
2013-10-03, 01:51 PM
The trouble is from a realism perspective is that our planet is very likely to be very different from wherever they called home.

That's one of the main areas where realism is going to be sacrificed for the story. I know that realistically, there aren't likely to be any planets that are close analogues of earth nearby, but for the sake of the game, there will be.


Even if they want to return to the hinterlands of their ancestors, even a small amount of resistance would mean they are better off using off planet resources to refuel, restock, repair, and then start accelerating to another system. Sure, it sucks for them, but their ancestors could take that leap into deep space, so why not them?

That could be a decent part of the story actually. Maybe they don't want to stay here, maybe they're just staying long enough to repair/rebuild their ship, resupply, and leave again. Of course that might take several years, and humanity might not realize they intend to leave at some point, so there would still be fighting. I'll have to think on that.

molten_dragon
2013-10-03, 02:00 PM
This has been done and published. Larry Niven and Jerry Pournell wrote Footfall several decades ago.

Yep, I've read it. It's one of the inspirations for the game.


Look, your aliens have to have a way to cheaply bring mass from ground to orbit, a power source capable of running a small city for decades without refuelling, a bussard ramjet capable of reaching c-fractional in the local bubble (Sol sits near the middle of a hole where interstellar hydrogen is 1/10th normal), and the capability to engineer a fully functional ark ship. You don't want to fight them, you want to sell them prime sea-side real estate! It is a good trade to give them half of Florida for that tech.

Well, much like the aliens in footfall, they aren't going to give us much of a choice about fighting them.


Plus, how did they manage to hide the massive EM signature and distortions of the ramjet? Why was the Earth surprised when there was a fusion torch spraying a characteristic and easily identified spectrum of radiation across the solar system for decades? We should have been sending messages trying to buy thier fusion technology for years before they even arrived. In Footfall these questions were avoided by having the aliens arrive in the 1950's, before we knew what to look for and while everyone was distracted bythe cold war, and hiding for thirty years.

Hmm, I hadn't thought of that. I'll have to give it some thought.

I would think that the ship would have to be fairly close for us to detect the exhaust. It would be much smaller than a star. I wonder if you could have a fairly narrowly collimated exhaust stream, and simply plan your braking maneuver so that it doesn't ever point at earth.

Lorsa
2013-10-03, 02:14 PM
A biological agent doesn't have to wipe out entire humanity, but it could be interesting if the numbers were more even and give a more "desperate" feel to the struggle as well as make the aliens seem more "evil".

warty goblin
2013-10-03, 02:17 PM
Why not have them be able to breed with humans and and want our women (or men) to repopulate their society?
Nothing against it from a literally law of physics perspective, but almost as absurd nonetheless.

Because that's probably a completely different story.

Ravens_cry
2013-10-03, 02:57 PM
Because that's probably a completely different story.
It's actually an old cliché for a motivation for an alien invasion, alines wanting our women. Having Earth be home-like enough to make it worthwhile to go through all the trouble of exterminating the existing intelligent species is almost as ridiculous.

Mr Beer
2013-10-03, 02:58 PM
The biggest reason I can think of to avoid orbital bombardment (that is, landing planetside instead) is due to the danger of setting of nuclear bombs.

I'm not sure if this is what you meant or not, but bombing a nuclear bomb won't cause it to detonate or at least won't cause the main explosion. It may set off the conventional explosive and scatter radioactive material around though.

molten_dragon
2013-10-03, 04:08 PM
It's actually an old cliché for a motivation for an alien invasion, alines wanting our women. Having Earth be home-like enough to make it worthwhile to go through all the trouble of exterminating the existing intelligent species is almost as ridiculous.

That's hardly true.

There are plenty of species that live on the earth that we can't breed with. It's not hard to imagine that there are alien species that could also live on earth but that we wouldn't be able to breed with.

Zavoniki
2013-10-03, 04:10 PM
This is kind of what I'm having trouble with too. I think that's why I'm basically going to go with psychological/societal reasons for why they aren't just wiping us out and landing once the dust settles.

What I'm thinking of is that the decision to attack us from surprise at all was a very controversial one, a significant minority of their population didn't support the idea. Which is why the decision was made to wage a limited war and negotiate from a position of strength, rather than trying to wipe us out. Basically those in charge worried that the minority who opposed an attack would go from disagreement to outright rebellion if they tried to wipe us out.

I like this idea, though this might be my love of Grey and Grey/Grey and Black morality. The Aliens show up, do some light initial bombardment, but have some law/moral reason for not using orbital bombardment. Going to why they left their solar system maybe their was a... Solar War? Each faction in their solar system went to war with another and used up their resources destroying each other, including massive use of orbital bombardment. Thus when they use it against humanity, it's a light touch, and most of their people get extremely angry about it. They destroy all our satellites, then land. Maybe they get a message out to us saying that if we don't use our WMD's they won't kill us all rocks from the sky. Then you have the more conventional war.

It's still a little awkward, like why aren't they using small objects that don't cause permanent harm to the planet, but I like the moral objection part. It adds something for the players to investigate/wonder about, especially if humanity wonders about it early. You'd have all these scientists telling the government we should all be dead but the aliens are being nice.

molten_dragon
2013-10-03, 04:16 PM
I like this idea, though this might be my love of Grey and Grey/Grey and Black morality. The Aliens show up, do some light initial bombardment, but have some law/moral reason for not using orbital bombardment. Going to why they left their solar system maybe their was a... Solar War? Each faction in their solar system went to war with another and used up their resources destroying each other, including massive use of orbital bombardment. Thus when they use it against humanity, it's a light touch, and most of their people get extremely angry about it. They destroy all our satellites, then land. Maybe they get a message out to us saying that if we don't use our WMD's they won't kill us all rocks from the sky. Then you have the more conventional war.

It's still a little awkward, like why aren't they using small objects that don't cause permanent harm to the planet, but I like the moral objection part. It adds something for the players to investigate/wonder about, especially if humanity wonders about it early. You'd have all these scientists telling the government we should all be dead but the aliens are being nice.

Yeah, I'm kind of thinking "Vietnam in Space". After all, just because the aliens have the capability to wipe us out doesn't mean they have the will to do so.

Telok
2013-10-04, 12:08 AM
I would think that the ship would have to be fairly close for us to detect the exhaust. It would be much smaller than a star. I wonder if you could have a fairly narrowly collimated exhaust stream, and simply plan your braking maneuver so that it doesn't ever point at earth.

There is one way to hide a fusion torch from the destination... But it will kick the alien tech level up some more.

You set your ranjet up so that it splits the exhaust stream into two to five separate streams aimed about a 20 degrees off from your direction of travel. This spreads most of your exhaust out of your direct line of travel. Let out a shadow shield on a cable and you should be mostly concealed from your destination.

The difficulty is that this cuts your thrust pretty nastily while putting rather a lot of compression on whatever you made your engine and supports of. That shadow shield is going to be an issue too, it's a bunch of... Nevermind. Just hang your living module behind the shield and you ought to be relatively safe from the hard radiation EM flux of the ramjet. It's still more massive and less efficent than you really want in a spaceship, but with enought hand-wavium it can work.

Mr Beer
2013-10-04, 12:50 AM
Yeah, I'm kind of thinking "Vietnam in Space". After all, just because the aliens have the capability to wipe us out doesn't mean they have the will to do so.

I think Space Vietnam is the best way to go. It's easy to utterly destroy humanity but if you stop short of that, you naturally have vastly superior tech vs. guerilla human resistance.

That kind of war is ideal for RPGing, since most military action is small group strategic strikes as opposed to mass war formations (which do very badly against superior tech anyway).

So you've got your reconnassiance missions, your capture/deliver the McGuffin, your rescue the important prisoner, your destroy the enemy outpost, your collect alien tech for analysis, your collect an alien for analysis...lots of possibilities.

Lorsa
2013-10-04, 02:53 AM
So you've got your reconnassiance missions, your capture/deliver the McGuffin, your rescue the important prisoner, your destroy the enemy outpost, your collect alien tech for analysis, your collect an alien for analysis...lots of possibilities.

So basically XCOM: Enemy Unknown?

Mr Beer
2013-10-04, 04:04 AM
So basically XCOM: Enemy Unknown?

Maybe so....

supermonkeyjoe
2013-10-04, 04:05 AM
If you want a winnable scenario how about this: the aliens tech is old, they've been travelling in a generational ship, some knowledge has been lost in that time , it's all in a database somewhere but none of the aliens are as well trained in their technologies as their forefathers that set out were. Maybe they can operate their drones and create more with some kind of automated factory device but if that is destroyed or stolen then the aliens either don't have the resources or knowledge to build any more.

Perhaps the thing that destroyed their planet was war, their colonies consisted of their home planet and several nearby moons/planetoids so they were already capable of spacetravel for travel between them, something happened and all-out war broke out, the alien species practically annihilated itself and destroyed all the planets capable of sustaining life in their system. The remnants of the species set off to one of the far flung planets that they observed may be capable of sustaining life, the ship that carries them is a converted vessel of another type and all they have in terms of a military force is what they could scavenge from the leftovers of the war, the population of the ship being mostly non-military or civilian survivors.

Depending on how long the wars went on for they could have a highly disparate level of tech, a collection of 'antique' railguns with maybe fewer modern projected energy weapons, the unmanned drones could be fairly new having recently been manufactured but may be using older alien scematics.

(This is now my headcanon for district 9)

Erik Vale
2013-10-04, 04:54 AM
(This is now my headcanon for district 9)

Didn't we see [at the end of the movie] a bunch more Prawn ships coming? However, for some reason I see a similar scenario for District 9, but more a case of stupid leaders and getting lost.

The_Tentacle
2013-10-04, 09:40 AM
Not really sure if this has been suggested yet, I skipped from page 1 to replying.

One recurring idea I see is that these guys are fleeing some greater "evil," which strikes me as a great idea. If you have a desperate battle for survival with one group and then the other, worse one shows up, it would be some great conflict. It may even lead to an alliance between the two sides who were previously fighting each other. Also, they're aliens, not everything they do has to be perfectly explained.

The Glyphstone
2013-10-04, 09:44 AM
If you want a winnable scenario how about this: the aliens tech is old, they've been travelling in a generational ship, some knowledge has been lost in that time , it's all in a database somewhere but none of the aliens are as well trained in their technologies as their forefathers that set out were. Maybe they can operate their drones and create more with some kind of automated factory device but if that is destroyed or stolen then the aliens either don't have the resources or knowledge to build any more.

Perhaps the thing that destroyed their planet was war, their colonies consisted of their home planet and several nearby moons/planetoids so they were already capable of spacetravel for travel between them, something happened and all-out war broke out, the alien species practically annihilated itself and destroyed all the planets capable of sustaining life in their system. The remnants of the species set off to one of the far flung planets that they observed may be capable of sustaining life, the ship that carries them is a converted vessel of another type and all they have in terms of a military force is what they could scavenge from the leftovers of the war, the population of the ship being mostly non-military or civilian survivors.

Depending on how long the wars went on for they could have a highly disparate level of tech, a collection of 'antique' railguns with maybe fewer modern projected energy weapons, the unmanned drones could be fairly new having recently been manufactured but may be using older alien scematics.

(This is now my headcanon for district 9)

So District 9 is basically Battlestar Galactica with aliens?

erikun
2013-10-04, 12:44 PM
I'm not sure if this is what you meant or not, but bombing a nuclear bomb won't cause it to detonate or at least won't cause the main explosion. It may set off the conventional explosive and scatter radioactive material around though.
The concern is not accidentally detonating nuclear warheads in their storage faculties.

The big concern is either humanity misunderstanding the initial alien attack, and thus launching nuclear missiles around the globe in a confused "retaliatory strike", or humanity correctly understanding the initial alien attack, and thus launching nuclear missiles in a panic. Either action would have roughly the same result: large-scale nuclear fallout due to multiple warheads going off, and making the planet uninhabitable. This would be why the aliens would want to take immediate control of any nuclear facilities, and why you'd find most governments quickly under their control.

GungHo
2013-10-04, 02:21 PM
What kind of cataclysmic event would drive a society that was capable of building a bussard ramjet to flee their home planet?
Same things that would get us.


Malignant AI superintelligence
Warfare with WMDs
Impact event
Overpopulation
Pandemic
Supervolcanoes
Megatsunamis
Bolide impacts
Geomagnetic reversals
Experimental misadventure
Gamma Ray Burst/Hypernova
Runaway climate change due to above items
Alien invasions of the alien's planet



What kind of weapons technology would be expected from a society with that level of technology?

Mass drivers/rail guns, nukes, directed radiation, electromagnectic pulses, chemically-propelled projectile weapons (i.e. guns); I'm going to assume that the physics will never be there for Star Wars/V pew-pew energy weapons.


If you were a member of such a society, how would you prosecute a war against earth, with the eventual goal of being able to live on the planet (or at least a good-sized chunk of it)
Assuming I have the intellegence to observe the planet with a sufficent degree of resolution and I know the difference between an F-150 and a tank, and I think you have a reasonable chance of seeing me coming... high-atmosphere fusion devices to end communications (I'm not here to sign up for T-Mobile family plans), and then I'd chunk bolides at every air base I could see. Probably would get some civilian airports doing that, but I'm going to assume I can figure out VTOL and so there's no need for me to use your air strips. I want to keep you 2D, and leave me with that 3rd D. Then I use arial UCVs to go at your naval and army bases. I can't get you away from your pop guns, but I can take your tanks away from you easily if they're all parked in one place. SAMs will be dangerous for us, but we can find all of the active radars, and for the passive systems... you don't have infinite numbers of those.

If I have no way of taking out large numbers of people efficiently via disease, I'd probably also take down major highway interchanges and bridges simply so I can better control your population's movement. Unless I need the infrastructure, labor, or... snacks, I'm not bothering with taking over large cities en masse, nor will I even attempt to lay siege. I'll simply wait for you to starve. It will take years, but your society is gone. You will be in a pre-industrial age at best. I will repurpose the power plants and the factories, and domestic connections will be severed. I will meanwhile recycle your cities block by block to work in a fashion that I see fit. The recycling teams will be automated and armed with firearms that work much like yours. If you move near it, it will detect you and shoot you until you stop moving.

Some of you will try to surrender and appeal to a sense of honor or decency we don't even perceive. Some of you will try to fight us and will find out that we have pretty good body armor and our light vehicles are as well armored as your heavy tanks. The rest of you will cower, and your last meals will be each other.


If they're relying on drones without a human-level AI, the aliens LOSE, hands-down. Unmanned combat vehicles have to be remote-controlled to be able to perfom basic friend-foe discrimination, let alone any sort of fancy combat maneuvering.
I imagine if they're capable of building UCVs and interstellar travel, they can put IFF on their crap.

Jormengand
2013-10-04, 02:48 PM
How to invade an alien planet (in this case: Earth). (http://tvtropes.org/pmwiki/pmwiki.php/JustForFun/HowToInvadeAnAlienPlanet?from=Main.HowToInvadeAnAl ienPlanet)

A lot of it is rather amusing (and it's TvTropes, so beware higher rating stuff), but it also has a lot of realistic considerations in it.

molten_dragon
2013-10-04, 04:40 PM
Same things that would get us.


Malignant AI superintelligence
Warfare with WMDs
Impact event
Overpopulation
Pandemic
Supervolcanoes
Megatsunamis
Bolide impacts
Geomagnetic reversals
Experimental misadventure
Gamma Ray Burst/Hypernova
Runaway climate change due to above items
Alien invasions of the alien's planet

Okay, taking these in order
- AI seems like a possibility, but I'm not sure how realistic it is given their technological development. It also seems like if their world was destroyed by a rogue AI, they're going to be very afraid of using drones.
- Warfare with WMDs could work, but it seems kind of, I don't know, pedestrian I guess. I was hoping for something more exciting.
- Impact event. I would think if they can find an earth-sized planet and determine it's inhabitable from 20 light-years away and have mastered space travel enough to actually go there, then they could detect any impactor large enough to render their planet uninhabitable pretty early, and do something about it.
- Overpopulation just doesn't make sense. How is sending 100,000 people offplanet in an ark ship a reasonable response to that? Just let your people die off until the population is back to a reasonable number, far more of them will survive.
- A pandemic doesn't seem very likely. It's not like it would render their planet uninhabitable. They wouldn't need to go to another star system, just hang out in orbit or on an asteroid base or something until they'd figured out a vaccine/cure for it and resettle the planet.
- Supervolcano or Megatsunami - I don't think either of these is a big enough event. It would certainly screw things up royally on their planet, but I'm not sure it would be apocalyptic enough to render it uninhabitable.
- Geomagnetic reversal. I'm not sure how this is supposed to be harmful enough to force them off their planet. It's happened numerous times here on earth and has never caused a mass extinction.
- Experimental misadventure is something I'm leaning towards, but what kind is the question.
- A Gamma ray burst would be too fast for them to do anything about and actually flee in time. A hypernova would wipe us out too, since we're so close.
- Runaway climate change. I thought of this but I didn't want to seem like I was making a political statement with the game.
- Other aliens invading I also thought about, but it seems like too much of a cliche.

captpike
2013-10-04, 04:46 PM
you could have something [scary sounding] pass close to their system, something that would give off huge amounts of radiation, they had time to build one ship before it got close enough to kill everything in their system.

having it be natural makes them more sympathetic then if they did it to themselves, like an AI or environment change. it also means they HAD to leave, they could not even say in their own system let along planet

eepop
2013-10-04, 05:15 PM
I would go with this:

1) Whatever calamity on their home spurs them to leave and come to earth
2) They build an ark ship, complete with AI, and send it to Earth.
3) They all go into some sort of stasis.
4) The ship arrives on earth, and the AI lands the arkship in a random spot. For whatever reason, it did not detect the indigenous life, and landed on top of a highly populated area on the eastern us seaboard.
5) They have advanced shielding on their ship, so they weren't all that worried about being overly careful with their landing, and it was a fairly energetic event. This kills humans in a reasonably wide swath around their landing site.
6) The AI sets about gathering what it needs to make the ship and immediate surroundings viable for the aliens to live in.
6b) Initial thoughts are that they breathe nitrogen, which Earth is great for, but the concentration in the air is actually too high. So they need to work out a way to filter out some of the nitrogen, but not all of it.
7) Humans react to what they see as an attack, and try to eliminate the threat, but the arkship is too well protected for their weapons to have much effect.
8) About a day later, the aliens start coming out of stasis, only to find that the AI has got them in a deep mess.
9) Some want to try to reason with the humans, others see that they are being attacked and feel they should respond in kind.
10) Even those that want to reason with the humans have to admit that they aren't currently able to communicate with this species they have never met before.
11)Its much more interesting for the aliens to not come in with some perfect knowledge of humans and how to cripple them. Its plenty to give them an impervious foothold and better technology.
12) If after seeing how humans fight, they realize how humans rely on oil they send out a drone along the gulf coast that destroys 95% of the refineries before it gets taken down, thats fine. It opens up adventure hooks outside of alien territory. Taking things like that by orbital bombardment just brings up all the questions that the thread has said time and again. You can still have it be nearly as one sided, but you leave yourself open to it not having to be one-sided when it suits you, and you don't have to answer the "why didn't they just orbital bombard everything?" question.

Terror_Incognito
2013-10-04, 09:33 PM
My work is very monotonous so I have HEAPS of time to think about stuff like this.

What if they are an entirely harmless species, surviving on their world through rapid reproduction, extreme altruism (old and sick throw themselves at predators) and superb communication (ultrasonic speech).


Depending on who you ask, our radio signals may not be detectible very far out.

Our radio signals might be very confusing to them images of violence interspersed with talking. Their culture places little value on individuals so maybe they think victims of warfare are sacrificing themselves as punctuation?

Maybe first contact involves them killing increasing prime numbers of people? The tech gap is closed because their weapons are the same as ours but with superior materials as they've never really needed weapons.

Ravens_cry
2013-10-04, 10:08 PM
My work is very monotonous so I have HEAPS of time to think about stuff like this.

What if they are an entirely harmless species, surviving on their world through rapid reproduction, extreme altruism (old and sick throw themselves at predators) and superb communication (ultrasonic speech).

Sounds like they could end up being terrifyingly xenophobic. War is a form of cooperation within the group after all.



Our radio signals might be very confusing to them images of violence interspersed with talking. Their culture places little value on individuals so maybe they think victims of warfare are sacrificing themselves as punctuation?

Maybe first contact involves them killing increasing prime numbers of people? The tech gap is closed because their weapons are the same as ours but with superior materials as they've never really needed weapons.
That's assuming the signals are even readable. Also, they might not recognize the video signals as such, much less be able to decode them into a visible image. Voyager 1 & 2's golden record included a cheat sheet to try and aid any finders, but there is none such for our radio transmissions.

Bucky
2013-10-05, 09:49 AM
Here are some more possibilities:
- A wandering red dwarf gets captured by their star, in an orbit that makes close passes to their planet. The solar wind strips their atmosphere over the course of a few decades, giving them just enough time to tech up to arcships but not enough to explore related technologies.
- The aliens left behind all their weapons and blueprints for weapons, but only due to limited storage capacity. The stuff they're actually using is improvised from industrial equipment - welding and cutting tools, explosive fuels and delivery rockets - or plundered from humans.
-The aliens are particularly dense and don't figure out about humans until they reach Earth orbit with not enough fuel to get back to the asteroid belt. But humanity as a whole doesn't realize there's a war on until the aliens have already landed. (this solves the orbital bombardment problem, mostly)

molten_dragon
2013-10-05, 11:30 AM
- A wandering red dwarf gets captured by their star, in an orbit that makes close passes to their planet. The solar wind strips their atmosphere over the course of a few decades, giving them just enough time to tech up to arcships but not enough to explore related technologies.

I like this idea. This and 'large scale industrial accident' are my frontrunners for why they had to leave.


- The aliens left behind all their weapons and blueprints for weapons, but only due to limited storage capacity. The stuff they're actually using is improvised from industrial equipment - welding and cutting tools, explosive fuels and delivery rockets - or plundered from humans.

This seems unlikely. With our technology, we could easily store petabytes of information in a ship that can hold 100,000 people. That should be plenty to store weapon blueprints.

Bucky
2013-10-05, 11:39 AM
This seems unlikely. With our technology, we could easily store petabytes of information in a ship that can hold 100,000 people. That should be plenty to store weapon blueprints.

Given that the planet you're going to is uninhabited, and you'll be on the road for thousands of years, which is more important: heavy weaponry schematics or a better selection of entertainment videos? Especially since the former increases the odds of your newly founded civilization self-destructing?

(alternatively, they brought the blueprints but haven't ramped up production; they need the resources to make factories for plasma cutters, delivery rockets etc. for colony building)

Gnoman
2013-10-05, 11:51 AM
This seems unlikely. With our technology, we could easily store petabytes of information in a ship that can hold 100,000 people. That should be plenty to store weapon blueprints.

If you were putting together a space ark to save a tiny remnant of the human race from extinction, would you choose to carry Tupolev over Tchaikovsky? It's not enough to simply save the people if you don't also preserve as much of the culture as you possibly can. Recordings and sheet music of the great composers, high-res scans of the works of the great painters, and the most important films, books and entertainment software (in short, all our greatest art) would take up immense amounts of storage space. If they don't anticipate the need to fight, it is incredibly unlikely that they would choose to save weapons. Not only that, but it would be extremely tempting to leave behind our legacy of war, and let the schematics for atomic bombs and the formula for Sarin die with our world. A space ark is the ultimate form of "Fling a torch into the future."

This idea makes a great deal of sense.

Toy Killer
2013-10-05, 04:22 PM
I've always like Neil DeGrasse Tyson's premise of Alien life forms not considering humans any different from, say, cows.

They come to earth, no known reason. They start to set up huge compounds minding their own business as people start to gather around to see what's going on. A few hoodlums or particularly brave people actually try to sneak into the compound and the aliens shoo them out or set up defensive perimeters. One nation, having it's people endangered decides it's had enough and sends a few tanks, an air raid or whatever.

They're done with taking our sh*t, and return fire. They don't bother with speciecide, with 6 Billion people, it's not worth the effort. Just destroy a few military compounds that are obvious, shatter some infrastructures, Oh that's cute, they have nuclear weaponry... I wonder if they have ever actually attempted to use it yet?

Dismiss us entirely as nothing but pest, with a few aliens very interested in how we have developed thus far. Would a scientist take any particular measure to learn to speak with a rat? No, at best it would utilize signals. Too much effort to speak to something that would have little meaningless things to say...

But that's my opinion. Admittedly, anything we look at is still in Plato's cave, and until we can see how life works on another planet, we will never know the possibilities or impossibilities of an extra terrestrial ecosystem. Therefore we can only look at the world in terms of what we know works.

but that's just my two copper.

Erik Vale
2013-10-05, 04:52 PM
-snip-

This would work, however I would only use it if the aliens were suppose to be extremely arrogant. I mean, from a aliens viewpoint cars could be a organism we have a symbiotic relationship with [think ants and aphids, or humans and cows], and skyscrapers could just be our to scale version of termite mounds.

Of course, I would only go this route with aliens that are for the most part rather stupid, or extremely arrogant.

Toy Killer
2013-10-05, 09:22 PM
This would work, however I would only use it if the aliens were suppose to be extremely arrogant. I mean, from a aliens viewpoint cars could be a organism we have a symbiotic relationship with [think ants and aphids, or humans and cows], and skyscrapers could just be our to scale version of termite mounds.

Of course, I would only go this route with aliens that are for the most part rather stupid, or extremely arrogant.

Well, for that, I will point to the common Brown Rat.

They invade our homes, eat our food, have sociable persona similar to humans (Albeit, primitively), and are particularly unimpressive intellectual when compared to a human.

They learn, think, expect future events, pass the blue ribbon test, etc. We don't go to war with them. We don't seek to eradicate all rats and concern ourselves with who is in charge of the rats. We just consider them a nuisance, some times a great nuisance, and occasionally a threat. But we don't go to war with them like we do with other humans that are in 'primitive' standing comparatively.

Steven Hawkings suggests that if we ever make contact with aliens, we should be extremely hesitant. He based that off of how humans have dealt with humans in lower technological standings.

Neil DeGrasse Tyson looks at how we treat Bonobo Chimps compared to humans. Chimps can fashion and use tools. We think that's cute. But when we want to develop land that is inhabited by chimps, we don't go to war with them. We don't make tactical strikes against leaders and cut off their supplies. We don't route them into ambushes and devise strategies for the local population.

We move in. We set up our structures. If the chimps get in the way, we put up walls, if they are still in the way, we kill a few and send a clear message.

If we're dealing with a species that can make interplanetary travel, why would they pay us any heed because we have an internet? They would find that cute.

Relevant Link (https://www.youtube.com/watch?v=KeJoVeKSsyA)

Erik Vale
2013-10-05, 10:43 PM
-snip-
To which I reply with three things:
-At what point did I say humans weren't remarkably arrogant? Arrogance and stupidity are two rather common traits in humanity [of course, what everyone believes to be stupid varies so who am I to say, however I will admit both to arrogance, niavity, and knowing less than I think I do at points]. If the OP was in a political mood, the aliens could be highly genetically and mechanically modified humans from the future who somehow accidentally went back through time [would explain how Earth looks good, perhaps they were part of a colony in a galactic empire]. However, given his desire to stay away from enviromental devestation due to politics/morals I doubt this will happen.
Also, I think that there would have to be a slightly larger than suggested tech difference for us to put it down to Man v Chimp [Kinda how the Guaold... I've spelled that wrong, view humans], more like English vs Australian Aborigional or American Military vs Middle East Terrorists.
Also, I believe we outnumber the proposed number of aliens by about 6*10^4. That makes the stupidity and arrogance aspect even bigger.

-As for mice, cool... But there an entirely different scale. If the aliens are several stories tall, then I agree with the comparison is relevant. Otherwise, it's not too useful to bring up.

-... I said there was a third point didn't I.... I seem to have forgotten it, I'll leave this here as a place holder for now, but I think it was something to do with us paying more attention to apes if they could nuke us.

molten_dragon
2013-10-06, 05:44 AM
If you were putting together a space ark to save a tiny remnant of the human race from extinction, would you choose to carry Tupolev over Tchaikovsky?

Absolutely I would. At that point, the people on that ship are all that's left of our race. When determining what to take and what to leave behind, you prioritize things that are going to help your species survive. They may not know earth is inhabited when they leave their home planet, but they know it can support life, so it's pretty likely that life is already living there. They have no idea what form that life might take. It could be huge vicious predators. Imagine if they had landed during the time of the dinosaurs. You'd certainly want weapons then.

Think of it this way. If your family was going to be stranded on an uninhabited island for the rest of your lives, which would you choose to take with you, a book on survival techniques, or your iPad full of music and movies?

I do agree with you that they wouldn't take a lot of actual weapons with them, since space will be at a premium and they won't need them during the trip, but they'll have time to build them once they're in our solar system before they attack.

erikun
2013-10-06, 12:59 PM
Neil DeGrasse Tyson looks at how we treat Bonobo Chimps compared to humans. Chimps can fashion and use tools. We think that's cute. But when we want to develop land that is inhabited by chimps, we don't go to war with them. We don't make tactical strikes against leaders and cut off their supplies. We don't route them into ambushes and devise strategies for the local population.
I think the biggest difference is how much of a threat the rats/chimpanzees are to humanity.

For the most part, the threat is relatively minor. A chimp isn't going to build a bulldozer and try to destroy a building. They're going to mess with wires and individual objects, and it is more practical to reinforce or replace the objects than it is to attempt mass extermination. There isn't a concern, because there isn't anything considered a thread. Compare this to wolf population in North America, which were practically eradicated because the people there thought that wolves were a thread.

Also, you can't declare war without there being something to declare war against. Even in human-human fights, it's always war against an established government or place with a centralized point of power. People do not declare war against, say, guerrilla groups or all the people in a specific area.

If aliens set up facilities on Earth and humans started dismantling them/killing the alien guards, then the aliens would likely view humanity as a threat and begin attacking it directy. If aliens had some sort of space-laser and were transporting material from the surface directly, or were mining something like the moon, then humanity's efforts to stop they would likely be very pathetic. They wouldn't consider humanity a threat, because when it comes to defense against people mining the moon, we really aren't.

warty goblin
2013-10-06, 01:47 PM
Also, you can't declare war without there being something to declare war against. Even in human-human fights, it's always war against an established government or place with a centralized point of power. People do not declare war against, say, guerrilla groups or all the people in a specific area.

The history of the last hundred odd years would suggest otherwise.

Gnoman
2013-10-06, 03:34 PM
Think of it this way. If your family was going to be stranded on an uninhabited island for the rest of your lives, which would you choose to take with you, a book on survival techniques, or your iPad full of music and movies?


I'd take the iPad, as long as I had a way to charge it. Mere survival is not enough.

molten_dragon
2013-10-06, 04:33 PM
I'd take the iPad, as long as I had a way to charge it. Mere survival is not enough.

Yeah, but the iPad isn't going to do you much good when you die of thirst because you weren't able to find clean water.

oudeis
2013-10-06, 04:35 PM
molten_dragon:

I don't think realism is practicable given the conditions you've established for this campaign. That is not a criticism: given the influences you've cited and the nature of the story dynamic you are clearly going for a more cinematic feel. I'd aim for 'truthinesss' instead; i.e., a level of Hollywood science that doesn't give the players cognitive hernias from trying to suspend their disbelief.

On the meta level, what are you ultimately trying to accomplish here? What do you see as the outcome of the campaign? You don't come across as some 'Gears of War', manlymachostubblefaceddudebrostudskickin'foreigner alienass mouthbreather, so I'm presuming you have some ideas beyond munchkin gunwankery. Unless you are writing/going to write a background on a par with one of the published gameworlds out there, where you want to take the plot is going to have a greater influence than scientific or military accuracy.

Toy Killer
2013-10-07, 12:33 AM
I think the biggest difference is how much of a threat the rats/chimpanzees are to humanity.

I think this is where we differ, immensely, actually.

I don't think we would be a threat. At least, that is the whole premise of conflict in alien invasion movies. We, literally, have nothing to harm them.

If a species were able to hop across solar systems comfortably, I doubt projectile weapons would scare them. Hell, they don't really scare people today (mass opinion aside). I mean, I'm a Corpsmen in the United States Medical Corps, Fleet Marine Force Medical Battalion. My job was treating bullet wounds, I would've had a different rate if they were half as lethal as people make them out to be.

Ballistics are a joke of weaponry. A bow and arrow is exponentially more lethal, but harder to train and use effectively. They are good for taking a combatant out of a fight, but not much else. Without medical attention, it can be more devastating. If they use rail guns, chances are they are familiar with ballistics and it is a dated weapon by their standards. And since knowledge is compounding, I doubt they would be seriously threatened by anything we have to offer.

Besides, people die of animal attacks pretty frequently. But we have yet to attempt to kill off any species deliberately (as in, the end of the species was the goal) aside from maybe mosquitoes (Which, fittingly, is responsible for the most deaths world wide).

It can be called arrogance on behalf of the aliens, but I think it's just being practical.

The Grue
2013-10-07, 01:06 AM
Also, you can't declare war without there being something to declare war against. Even in human-human fights, it's always war against an established government or place with a centralized point of power. People do not declare war against, say, guerrilla groups or all the people in a specific area.

http://cdn.memegenerator.net/instances/400x/38466770.jpg

Toy Killer
2013-10-07, 01:12 AM
Oh, and in agreement with Grue...

The People of East Timor would like to have a word with you...

Clistenes
2013-10-07, 04:16 AM
The situation being as the OP depicts, the smartest thing would be to use powerful nukes to blow the cities of the most industrialized and technologically advanced of Earth's nations to get rid of the most dangerous opponents, and then land and colonize some third world countries unaffected by the nukes.

I would expect them to use lots of EMP weapons to cripple the armies of the third world countries they didn't nuke, combined with chemical weapons and robotic bombers to kill the soldiers.

They would try to completely get rid of all humans using biological weapons, like, for example, artificial retroviruses.

Hubert
2013-10-07, 05:43 AM
I don't think we would be a threat. At least, that is the whole premise of conflict in alien invasion movies. We, literally, have nothing to harm them.

In this context, the aliens are coming on earth to take control and settle on the planet. Even if we cannot directly harm them, we still have the potential to substantially damage the planet itself. Rats and chimpanzees cannot claim this kind of 'feats'.

GungHo
2013-10-07, 10:14 AM
- Experimental misadventure is something I'm leaning towards, but what kind is the question.
When I was thinking of this I was thinking of things like what was worried about when we started testing things like the LHC, the Tsar Bomba, or the nastier chemical/biological weapons... basically that we were screwing with things that would end up creating black holes or irradiating/befouling the planet beyond all hope of recovery. The AI thing as well.


- Runaway climate change. I thought of this but I didn't want to seem like I was making a political statement with the game.
It's not a political statement if the reason for the change is due to a calamatous event rather than "we ate all the space-cows, so you need to save your earth cows". It's more back at the misadventures, WMDs, Deccan-trap-like volcanism, and impact events which have caused or were theorised to possibly cause climate change that lasted/could last for decades or centuries. There's a reason you don't speak dinosaur.

Hell, it could have even been something that happened while they were in space, and they ended up not being able to come back home, like in Odyssey Five, Battlestar Galactica, or Planet of the Apes.

Jay R
2013-10-07, 10:34 AM
People do not declare war against, say, guerrilla groups or all the people in a specific area.

While technically true, this is scant comfort to the passenger pigeons, dodos, Eastern Elks, aurochses, and other species who weren't dangerous, just occupying the land we wanted.

I'm not concerned with extra-terrestrials who war on us as equals, but those who displace as mere vermin.

Eric Tolle
2013-10-09, 05:27 PM
Interesting topic. Here's a few notes:

Bussard ramjets are an ultimate technology, especially if they are effective enough to actually act as more than a brake. They are also incidentally, limited to about 12% lightpeed. Plan travel times accordingly.

A Bussard ramjet pretty much demands a developed interplanetary civilization, so a planetary level disaster would be irrelevant. It has to be something that takes out civilization on a star system scale, something that is so terrifying they couldn't just retreat to the Oort cloud and start over. There's only a few scenarios I can think of that match those qualifications, which basically boil down to a) an "Accellerando" scenario, or b) a "Killing Star" scenario. So either uncontrolled AI is converting the home system into computronium, or somebody is destroying their owners and guests from interstellar distances. Maybe somebody is crying their planets from several thousand light years away using a Nicoll-Dyson laser. Whatever.

The above brings up the possibility that the aliens could be invading to save us, and themselves as well. They arrive fleeting the destruction of everything, and here we are tossing around, radiating radio waves into space, and experimenting with AI. This obviously needs to stop, Right Now.

Fortunately for the humans, it's not as easy to move an asteroid as people believe; it takes the same amount of delta-v as it does to move a similarly sized rocket, sui expect asteroid assaults to be a last-ditch effort that would take many months or years top accomplish. Unfortunately for the humans, if the aliens just park in a high orbit, they are going to be pretty much immune from attack. "Thor" settle attacks may be inaccurate, slow, but effective against immobile targets.

Also, the aliens may only need to do an orbital pass to civilization. Maybe.I haven't done the math, but the magnetic field for a Bussard ramjet may be strong enough to do nasty things to unshielded electronics on a global scale.

Alternatively, you might just do an " English in New Zealand" scenario, where the aliens don't care about humanity as a whole, but are willing to trade technological toys to natives with unusual resources they might want. " These cacao beans have a delightful effect on our central nervous system. So local chieftains of these Central America and West Africa areas, for ten tons of beanswe'll trade you a device that will induce fusion reactions at range."