RAR Martians Invade Earth!

[Ryan Thunder]

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?

[Samuel]

Asteroids. That is all. Once the human population is reduced from your orbital bombardment, claim the world.

[The Romulan Republic]

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.

[Samuel]

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.

[The Romulan Republic]

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.

1. You have to have a way to stear them. What amounts to a propulsion unit for a large space craft is not going to be cheaper than some nukes.

2. You'd think that with their tech, mountain ranges wouldn't be a huge inconvieniance.

3. Depending on the asteroid, that dust cloud will be around for a long time right? Which means the planet will be cooled, crops killed, and the environment wrecked. I doubt the long term effects of one (or one hundred) nukes are going to be any worse. Asteroids on the scale you're talking about are to nukes what nukes are to conventional bombs. This is overkill if you want the captured planet to be worth much. At least tactical nukes would leave something if used in limited numbers. Unless of course these aliens are into genocide for laughs.

[Samuel]

1 The warhead is the expensive part.

2 Why? We are high tech and mountain ranges are still a huge problem.

3 It helps eliminate the problem of "plucky resistance fighters". I'm assuming the are pure evil since there really is no reason to conquer Earth anyways.

[The Romulan Republic]

1 The warhead is the expensive part.

As compaired to a space craft's drive system?

2 Why? We are high tech and mountain ranges are still a huge problem

Well, if their's nothing valuable to them in the mountains, they'll just fly over them (might cost them a little fuel). If their is something, they won't want to flatten them. Its not like they have pre-existing cities in the mountains they have to be able to reach, like we do.

3 It helps eliminate the problem of "plucky resistance fighters". I'm assuming the are pure evil since there really is no reason to conquer Earth anyways.

Right, because fighting an unessissary war="pure" (comic book?) evil.

I can think of a number of reasons for them to attack as well. One, Mars is no longer able to support them due to environmental reasons, so they want Earth. Two, religious motivations (ie, spread the word of the Martian God). Three, they see us fucking ourselves over, and view their invasion as a "humanitarian" intervention. Four, political war of distraction, under some bullshit excuse (maybe they got their population all worked up over our "espionage robots"). All of these reasons would have precidents in human history.

[Samuel]

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

2 It makes life easier. That is the important part.

3 Curse you and your valid argument!

1 wouldn't work though- if you can get the population into space craft that can sustain them, you have space colonies. No need for living space.

[The Romulan Republic]

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

Doesn't mean they're cheaper than warheads. But its a valid point.

2 It makes life easier. That is the important part.

Leveling a mountain range does not make life easier unless you don't care about destruction. I'm presuming that they are more likely to want the world reasonably intact. Also, 100-mile craters are not convieniant either.

3 Curse you and your valid argument!

1 wouldn't work though- if you can get the population into space craft that can sustain them, you have space colonies. No need for living space.

I see the point. Though a planet can support more people than colonies built with "slightly better than human tech."

[Darth Hoth]

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?

I would think competition between factions is good for development; it forces progress, in that the states will compete and develop technology to match or outshine their rivals. A world government would lack much of this incentive to constantly improve, and could easily grow stagnant without external threats.

If their technology is only a couple of years or so ahead of ours, I would say no, they cannot fight us effectively. Travel times are sufficiently long that we can prepare and intercept the weapons they send against us, and transporting massive amounts of troops or war-robots is not practical for obvious reasons.

[The Romulan Republic]

Actually, I will acknowledge that they almost have to use WMDs to succede, or at least be willing to if threats fail. A conventional invasion will be absurd. Consider how many troops its taking the US to maintain control (barely) over Iraq. Now multiply that to an entire planet. With tech only slightly better than ours, how can they hope to pull off an invasion on that scale over those distances?

Even still, troop numbers will be a big problem. If they force Earth into a surrender by threatening use of WMDs (perhaps with a demonstration on a city), then any surface bases they establish will still be potentially exposed to terrorist attacks from Earth insurgents. Now depending on their reasons for war and how desperate they were to win, they might be willing to simply use nukes or asteroids, but if they want the planet intact then it isn't going to be an option. So what do they do?

One option, if they just want the human's cooperation for whatever reason but not full scale bases or collonization, would be to just stay in orbit, and engage in limitted exchanges with the humans on the surface, having the humans ship whatever they want up under threat of bombardment.

If they want to establish a pressence on the surface, and are ruthless enough to simply exterminate the human resistance (obviously their internal politics, culture, and reasons for attacking Earth would all come into play), here'a possible, and rather devious, option. Procede as above, but collect DNA from their human emissaries on each visit, and use it to develope a bioengineered weapon that targets only humans. Then claim the planet with limitted colateral damage.

[Strider]

Short of dropping rocks or nukes, there really isn't much they can do. Any troops they could reasonably be able to send here would be hopelessly outnumbered; they have absolutely no chance of taking and holding territory. The supply line problem is a killer, since they not only have to pack an army onto their ships but the supplies for an army in the field. Lastly, and perhaps most importantly, the fact that they are invading Earth means they want it in reasonable condition; no such stipulation ties Humanity's hands when it comes to Mars. If and when humans stole the necessary tech from the Martians, you'd better believe they would drop some pretty awful shit down on the Martians' heads.

The only type of interplanetary war that really works between similar civilizations is a War of Annihilation.

[The Romulan Republic]

Short of dropping rocks or nukes, there really isn't much they can do. Any troops they could reasonably be able to send here would be hopelessly outnumbered; they have absolutely no chance of taking and holding territory. The supply line problem is a killer, since they not only have to pack an army onto their ships but the supplies for an army in the field. Lastly, and perhaps most importantly, the fact that they are invading Earth means they want it in reasonable condition; no such stipulation ties Humanity's hands when it comes to Mars. If and when humans stole the necessary tech from the Martians, you'd better believe they would drop some pretty awful shit down on the Martians' heads.

The only type of interplanetary war that really works between similar civilizations is a War of Annihilation.

If they gain orbital superiority first, how the hell are we supposed to hit them?

Absent the abillity to deploy a large ground force, however, they do need to use at least the threat of WMDs to coerce cooperation.

[K. A. Pital]

Postulate one: realistic technologies.
Postulate two: we are at our current level.
Postulate three: they are gearing for interplanetary warfare (i.e. they know of us but we know of them not).
Postulate four: Martian civilization is hiding from us. They probably utilize nuclear power, oil or coal would result in too much of observable pollution and emissions, unlike nuclear undergound megaplants.

Result: the Martians are most likely to field Orion ships as primary means - if they are going for deploying troops in meaningful numbers. The implications of this are painstakingly clear - they can nuke the Earth into submission, remaning in safety of huge interplanetary Orion cruisers.

Orbital superiority of Martians is clear. Human satellites are wiped out within the very first days of an attack by incoming Orion cruisers, later on those cruisers systematically demonstrate the Martians' power. Maybe on sparsely inhabited or even non-inhabited territories.

Earth cooperates. Martian troops start landing to unite Earth under the glorious banner of United Mars (or whatever their planet-state is called). And that's when they will have to deal with a massive insurgency...

Orion ships are possible technology and could have been fielded by Earth in the 1970s already if not for the nuclear test bans. They are potent means of large-scale interplanetary and even interstellar travel.

[Mr Bean]

People forget that moving shit in space is easy.

The Romulan Republic, did you know there are plans underway for diverting incoming Asteroids using nothing but the gravity of the ship? Even easier, something the size of an Apollo lander landing on an rock then using it's built in engines can move Asteroids two or three miles across fairly easily. And a rock that size(If accelerated enough) can hit for a Gigaton level strike.

Face it any Mars VS Earth Scenario devolves into "Who can drop rocks first" Taking Stas Bush's example if they head here with Orion spacecraft and take out the satellites and then drop a medium sized rock on say an empty part of Siberia or Canada and announce in advance what's going to happen. The Asteroid belt as noted elsewhere has over two hundred "planet killer" sized rocks sitting it ready to use.

Hell if you had something along the lines of tow ropes you can use the invasion ships to move the rocks into orbital position. Remember they don't need to hit earth at any speed. All they need to do is move the rocks into Earth's orbit and let earth's own speed to the impacting for them.

[Imperial Overlord]

People forget that moving shit in space is easy.

The Romulan Republic, did you know there are plans underway for diverting incoming Asteroids using nothing but the gravity of the ship? Even easier, something the size of an Apollo lander landing on an rock then using it's built in engines can move Asteroids two or three miles across fairly easily. And a rock that size(If accelerated enough) can hit for a Gigaton level strike.

Moving a ship to the belt and back isn't free in either time or resources, but it's really side discussion. Once they have orbital superiority they can drop rocks or nukes on us as they see fit. They'll be able to pull off both and it's really an issue of what goes over better with their bean counters and the state of their weapons stocks.

[K. A. Pital]

Hell if you had something along the lines of tow ropes you can use the invasion ships to move the rocks into orbital position.

Yeah. They could drop one into the ocean just for gigs.

And even if they do not have nuclear-powered interplanetary vessels, they just need to spend around 10-20 years prior to invasion meticulously placing space tugs in the asteroid belt, so taht when time comes they will have dozens of such bombs.

[Ryan Thunder]

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.

[Bilbo]

If they are only slightly ahead of us tech wise is that enough of a lead for power armor? If not then you can throw any type of ground invasion. Mars only has 38% of Earths gravity. That means that every martian soldier that lands on Earth finds himself and his hear weighing more than two and a half times more than it did back home. Without some sort of powered armor there is just no way martian soldiers are going to move well much less fight effectively in that situation.

Now lets assume that they have power armor that makes them two as strong as normal. They are still weaker than the normal human being on Earth. Imagine the horror when they realize that the average human soldier can snap a Martian in half over his knee.

With this in mind I cannot imagine the Martians wanting to claim Earth as a colony. Which means they want it for its resources. Which means you need to keep human infastructure and populations in place to gather those resources while you threaten from orbit.

[Broomstick]

Actually, I will acknowledge that they almost have to use WMDs to succede, or at least be willing to if threats fail. A conventional invasion will be absurd. Consider how many troops its taking the US to maintain control (barely) over Iraq. Now multiply that to an entire planet. With tech only slightly better than ours, how can they hope to pull off an invasion on that scale over those distances?

Is it just me, or is anyone else considering that Earth gravity is what, three times Martian? How well do you think OUR troops would fare on a world with three times Earth gravity? Not to mention that, presumably, Martians will have evolved for Martian conditions and would find Earth temperatures prohibitively hot outside of our polar regions and the atmosphere a hundred times denser than what they are used to.

Other than the total destruction of Mars as a useful planet I can't conceive of WHY they would want to invade Earth. Destroy humans if they're perceived as a threat, yes, I can see that, but that doesn't require an invasion or occupation, it just means you kill all humans - orbital bombardment, bioweapons, whatever. For a species adapted to Mars, Earth is pretty useless for living purposes.

[Bilbo]

Actually, I will acknowledge that they almost have to use WMDs to succede, or at least be willing to if threats fail. A conventional invasion will be absurd. Consider how many troops its taking the US to maintain control (barely) over Iraq. Now multiply that to an entire planet. With tech only slightly better than ours, how can they hope to pull off an invasion on that scale over those distances?

Is it just me, or is anyone else considering that Earth gravity is what, three times Martian? How well do you think OUR troops would fare on a world with three times Earth gravity? Not to mention that, presumably, Martians will have evolved for Martian conditions and would find Earth temperatures prohibitively hot outside of our polar regions and the atmosphere a hundred times denser than what they are used to.

Other than the total destruction of Mars as a useful planet I can't conceive of WHY they would want to invade Earth. Destroy humans if they're perceived as a threat, yes, I can see that, but that doesn't require an invasion or occupation, it just means you kill all humans - orbital bombardment, bioweapons, whatever. For a species adapted to Mars, Earth is pretty useless for living purposes.

HA! Beat you by less than a minute.

[Broomstick]

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!

[Solauren]

Geeze, you are all OVERTHINKING IT.

All you need to do to have a successful interplanetary invasion is 1 genetics lab, a group of scienists, and a scout ship to collect specimens.

Make up a virus that affects the target population, and a cure. Unleash said virus. Sit back, watch as said virus devestates planetary population. Arrive in the spirit of peace, offer the cure. The price is joining the Martian Empire.

Earth is conquered, and all it costs was some medical R&D.


Intercepting that kind of invasion would be damn hard too. One scout craft could come in at a 90 degree angle to the orbit of the planet (polar), where we don't do alot of looking (say Antarctica), fly low over the oceans, and then go raiding on some isolated island. They then leave the same way, and there is a good chance of them not even being spotted.

They return with the virus the same way, and no problems.


In short, provided we are not invaded but cosmically stupid aliens, and don't have a crashed alien ship a TV Network Service Tech can play around with, we're boned. Pure and simple. Even if the enemy tech is only 20 - 30 years more advanced then we are.

I for one, welcome our new Martian Overlords. I'd like to remind them that I'm useless and should be overlooked.

[Darth Hoth]

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.

[Sky Captain]

Intercepting that kind of invasion would be damn hard too. One scout craft could come in at a 90 degree angle to the orbit of the planet (polar), where we don't do alot of looking (say Antarctica), fly low over the oceans, and then go raiding on some isolated island. They then leave the same way, and there is a good chance of them not even being spotted.

Damn hard with near future technology, I cant imagine any non radiation spewing drive that would allow small scout craft to pull of this kind of maneuver. Nuclear salt water powered space shuttle may do it, but we are going to notice trail of radiation it leaves in our atmosphere.

But I agree, engineering some sort of bioweapon is only way to depopulate Earth without wrecking the environment and destroying infrastructure. Any conventional invasion is going to fail because of low martian troop numbers and human insurgencies.