RAR Martians Invade Earth!

[Bilbo]

I think you underestimate humanity's resolve, or possibly overestimate the possible effectiveness of the bioweapon. I also question the viability of landing, let alone launching, a spaceship without Earth authorities noticing.

If Martian physiology is very different from our own and it would be considering the Martian environment then it could be decades or longer before a viable bio-weapon could be created. You would first have to understand how humans work and how our immune system works.

[Bilbo]

Ah, but you MISSED the vastly greater terrestrial atmospheric pressures! That can't be good either, especially with all that corrosive free oxygen - why it's nearly 20% of the Earth's atmosphere!

The pressure part can be overcome much easier than the gravity. If it was just pressure then a pressure suit will protect you. But the gravity is a killer. Means either heavy combat powersuits, heavy bionics, or genetic engineering for the Earth environment.

[Samuel]

1 If they can build a large enough fleet to invade, than yes, drives are relatively cheap.

They have only slightly post-modern technology. Stuff you might expect to see in the next 20-30 years, at best.

So, drives are only as "cheap" as they are for us.

Current chemical drives are cheap- the fuel costs are only in the tens of thousands. Someone mentioned it on another board that it was only 20,000 if you started mass production.

Of course, if they are using nuclear drives, than dropping nukes would be simpler.

[Patrick Degan]

They don't need to use asteroids. They could just as easily use nukes from high orbit. I doubt we have anything that can shoot high enough to reach them their.

Asteroids are cheaper and Mars is near by the belt. Plus, you can terraform with asteroids, removing pesky mountain ranges. And there isn't an fallout AND the dust raised can block out the Sun.

Mars is about 100 million miles from the periphery of the asteroid belt. But then, why go there for the rocks you want to drop on Earth when there's a ready source right nearby the target —Earth's moon. Set up a simple mining operation and a few mass-drivers and you can bombard the planet at will.

But then, if the Martians are having to evacuate their planet, and Earth presents a problem in terms of gravity and atmospheric pressure for habitation, why not occupy Earth's moon and set up colony domes there? Lunar gravity is about half Martian gravity and they can formulate the atmosphere within their domes to their exact standards. They get near-unlimited solar energy (unless they opt for all-nuclear power) and plenty of space for cropping, and materiel not only for their colony bases but in future for orbital habitat construction as well. From a Martian perspective it would make more sense to take over the Moon than the Earth.

[The Romulan Republic]

1 If they can build a large enough fleet to invade, than yes, drives are relatively cheap.

They have only slightly post-modern technology. Stuff you might expect to see in the next 20-30 years, at best.

So, drives are only as "cheap" as they are for us.

Current chemical drives are cheap- the fuel costs are only in the tens of thousands. Someone mentioned it on another board that it was only 20,000 if you started mass production.

Of course, if they are using nuclear drives, than dropping nukes would be simpler.

Do you have a credible source for that? Because that sounds rediculously low.

[Samuel]

My source is Sikon, from this thread:

http://bbs.stardestroyer.net/viewtopic. ... 8&start=25

Current rockets are expensive with figures ranging greatly from $3000 / kg for the Proton to $57000 / kg for the Space Shuttle, in part a result of a basic production and operations cost of millions to billions of dollars being amortized over a handful of tons per year. For example, a launch of the Atlas D used about $0.04 million of kerosene and liquid oxygen, converted to today's dollars, while the rocket itself cost $27 million ... a launch cost exceeding fuel and energy expense by three orders of magnitude. Since the Atlas is not reusable, its cost is not amortized over multiple launches.

Opps- that is 40000 dollars. I don't know the cost for the drive itself.

[The Romulan Republic]

Wow, I had no idea that the rocket was so much more expensive than the fuel. It makes me all the more pissed that we're still using expendable rockets.

[K. A. Pital]

Expendable rocket costs are falling. But as I said, Martians will probably use Orion ships since they don't have test ban treaties and the like.

[The Romulan Republic]

Expendable rocket costs are falling. But as I said, Martians will probably use Orion ships since they don't have test ban treaties and the like.

How do you know? Maybe their are hippies on Mars too.

[Coyote]

They send their Chtorrans to eat us.

[K. A. Pital]

Maybe their are hippies on Mars too.

You see, they are single nation-planet, they do not have the possibility of nuclear war between them looming - but there's a possibility of interplanetary nuclear war.

It makes all the sense for them to prop orbital weapons and Orion ships are the fastest way to orbital supremacy. It made sense for us to hinder development of orbital weapons since they disrupted the military balance and could allowed a nation to launch a deadly first strike with orbitals.

[Swindle1984]

Wow, I had no idea that the rocket was so much more expensive than the fuel. It makes me all the more pissed that we're still using expendable rockets.

The rockets are often retrieved anyway so they can be recycled. That and just letting them float in the ocean was hurting NASA's image with the tree-huggers.

The Martians wouldn't ever need to land, except to send ships to pick up whatever we give them in tribute. You only need WMD's for the first demonstration, and possibly to use against whichever major power actually tried firing nukes at you as a further demonstration. After that, just use the Rods From God and drop crowbars made of tungsten on targets from orbit. Got a tank, grounded aircraft, building, or group of insurgents you want to take out? BOOM. All the witnesses know is that SOMETHING from space hit the ground and now there's a crater where the folks who just pissed off the Martians used to be.

Because we aren't geared for combatting threats in space (minus a bare handful of missiles designed to shoot down spy satellites), as long as the Martians have orbital superiority, they're going to kick our asses. Landing ground troops is out of the question for them. Heck, the Martians are probably chemically different from us too; not only would gravity and pressure be a bitch for them, but the atmosphere would likely be toxic. If Larry Niven had been correct about the ecosystem of Mars, then Martians would spontaneously combust on contact with atmospheric water. Who knows how real Martians would like our atmosphere.

So basically, our planet is completely uninhabitable. It would be like us trying to invade Mercury. It doesn't make any sense. The only reasons for the Martians to attack us would be to exterminate us (because we're a potential threat, or their religion(s) finds our very existence offensive, or they're just xenophobic assholes.) or to extort our natural resources from us and obtain rare elements that way. I'm betting Mars and the asteroid belt don't have much in the way of radioactives like uranium or plutonium.

The only chance we would have of resisting would be to secretly build one or more Orion's and catch them by surprise, which isn't likely at all, or to sneak a shit-load of explosives into one of the shipments of loot they've extorted from us under threat of being nuked from orbit. And hope they don't check the things out first with bomb sniffers or geiger counters (depending on what sort of bomb we use). They likely wouldn't need more than one big ship and a handful of landers, so if they're anywhere near as anal as our bean-counters are they might not have more than one mother ship. Get a big enough bomb on board and there, problem solved, at least temporarily.

[The Romulan Republic]

If they only had one ship, and we took it out, how long would we have to prepare for the counter attack?

Not long enough, I fear.

[Shroom Man 777]

@ Solauren:

Why could the aliens engineer a bio-weapon against us? They'd have to obtain human samples and do extensive experimentations to create an effective bio-weapon. They'd have to come here to do it, with a space ship. What if their ship is spotted and shot down, and we end up with a couple of Martian corpses to do bioweapons research on?


It would be awesome if, because of their unified government, the Martians have ended up forgetting a few concepts of war and so we end up being the more effective killers - with more nukes. We win.

[Solauren]

@ Solauren:

Why could the aliens engineer a bio-weapon against us? They'd have to obtain human samples and do extensive experimentations to create an effective bio-weapon. They'd have to come here to do it, with a space ship. What if their ship is spotted and shot down, and we end up with a couple of Martian corpses to do bioweapons research on?

Which I addressed at using a Southern polar route (anyone with a telescope can see we have nothing down there), followed by a fast, low altitude approach to an isolated island. That would maximize the chances of avoiding detection.

Also, by taking that approach, you minimize the amount of land the vessel could crash on. It would be rather difficult to recover a crashed alien ship from the bottom of the pacific ocean (especially if it also self-destructed).

You also assume we have the technology to detect and shot them down. Imagine what Stealth technology will look like in 20 - 30 years with some of the findings that are being announced.

[/qoute]It would be awesome if, because of their unified government, the Martians have ended up forgetting a few concepts of war and so we end up being the more effective killers - with more nukes. We win.[/quote]

Which completely negates them invading us, now doesn't it?

[phongn]

Wow, I had no idea that the rocket was so much more expensive than the fuel. It makes me all the more pissed that we're still using expendable rockets.

It's even more expensive to use a reusable one. There is no such thing as a free lunch.

[K. A. Pital]

It's even more expensive to use a reusable one.

By that you meant it's more expensive to make one. Using one is cheaper, since you don't need to re-build the whole thing again and again. This is very economic for super-rockets (Energia family), this is why reusable versions of those were proposed, and the rocket was semi-reusable. When each launch lifts over 100 tons into orbit, you might as well think about re-using such a potent booster.

[cosmicalstorm]

Say that a species of roughly equal intelligence to our own has been developing at a similar pace to humanity in secret on Mars. Never mind how.

Say they decide to invade Earth. They're a bit more technologically advanced than us due to having a unified world government while we're all divided into factions, but we'll limit them to plausible technologies that have been proposed here for development but haven't necessarily been put into production.

For example, their ground troops might have something equivalent to an M8 or SCAR-H for their basic rifle.

The Martians are as populous as we are, and begin on Mars. They've managed to hide from the various Mars lander probes that have been sent there to date, so if we want to detect them, it will have to be en route.

So, in short, could an interplanetary invasion be successful with modern and near-future technology?

If you haven't read Footfall yet you really ought to pick it up soon. It deals with almost this exact scenario. Though I think the F'tiph are from Alpha Centauri.

[Vultur]

There are hard limits to how deadly a disease can be; if it's too deadly, it doesn't spread (because the carriers are dead). Ebola is already deadly enough to be having problems with this - it actually got to the US once (a small planeful of people, I think 20, from Africa landed in Virginia with it) but the infected people died before they could spread it. EDven artificial diseases will still be limited by this.

I think a lot of Earth governments would be brave (or murderously stubborn, depending on how you look at it) enough to refuse the bioweapon-antidote-in-return-for-takeover ploy. We'd be looking at 30%-50% death rates maybe (that's pretty generous; the Black Death was about 33%, and that was affecting a population with no medical knowledge.) I think 50% of the population would be enough to keep a modern industrial society going, since bioweapons don't destroy infrastructure.

[Mr Bean]

There's a serious flaw in your logic there Vultur in that it assumes you can spread the anti-dote just as quick as the disease. By it's nature(Infect times, dormancy, partial resistances) if you dumb some kind of super-virus into the air or water or what have you, by the time you have a nice sized infection group it's going to be logisticly impossible to deliver the same anti-dote unless you have a massive amount of space-ships.

And if you do, it makes more sense to throw rocks at us then engineering a fancy bio-weapon. Yes they could launch a bio-weapon at us, or else? Again time and effort is greater than rocks.

[Ryan Thunder]

There's a serious flaw in your logic there Vultur in that it assumes you can spread the anti-dote just as quick as the disease. By it's nature(Infect times, dormancy, partial resistances) if you dumb some kind of super-virus into the air or water or what have you, by the time you have a nice sized infection group it's going to be logisticly impossible to deliver the same anti-dote unless you have a massive amount of space-ships.

And if you do, it makes more sense to throw rocks at us then engineering a fancy bio-weapon. Yes they could launch a bio-weapon at us, or else? Again time and effort is greater than rocks.

Because neither of the popular solutions (rocks, bioweapons) are terribly exciting, I'm going to make them impossible.

They have to land troops and take control directly. They can communicate with us.

What happens?

[Samuel]

There's a serious flaw in your logic there Vultur in that it assumes you can spread the anti-dote just as quick as the disease. By it's nature(Infect times, dormancy, partial resistances) if you dumb some kind of super-virus into the air or water or what have you, by the time you have a nice sized infection group it's going to be logisticly impossible to deliver the same anti-dote unless you have a massive amount of space-ships.

And if you do, it makes more sense to throw rocks at us then engineering a fancy bio-weapon. Yes they could launch a bio-weapon at us, or else? Again time and effort is greater than rocks.

Because neither of the popular solutions (rocks, bioweapons) are terribly exciting, I'm going to make them impossible.

They have to land troops and take control directly. They can communicate with us.

What happens?

Welcome to Planet Iraq.

[Ryan Thunder]

It won't be uniformly like that, however. Who do you think is going to give them the most trouble?

[Vultur]

If they have to land troops, they lose. There's no way they could ship significant numbers with near-future technology. If they completely bankrupted their planet's resources (if it was a last-ditch do-or-die thing) they might get a few hundred thousand here. Maybe more with Orions, maybe. But with roughly equivalent technology, it would take hundreds of millions to conquer Earth, probably more.

[Samuel]

It won't be uniformly like that, however. Who do you think is going to give them the most trouble?

Anywhere they land. If they don't use their orbital advantage, the world will unite and move troops to their landing sites. We could beat back anything less than 10 million without increasing our existing troop strength.

Unless they set up a teleporter, in which case things get... fun Until we nuke it till it glows that is.