[What If} Massive Killer Asteroid to Hit Earth in 50 Years

[Stark]

Dude, the planet is either going to be disrupted or the crust is going to melt. Bunkers will be useless (unless they're actually lava-boats).

I doubt a colony of a few thousand people is viable long-term, so it's a complete waste of time, the species is still doomed.

[GrandMasterTerwynn]

Dude, the planet is either going to be disrupted or the crust is going to melt. Bunkers will be useless (unless they're actually lava-boats).

I doubt a colony of a few thousand people is viable long-term, so it's a complete waste of time, the species is still doomed.

Why wouldn't it be viable? I believe the minimum size of a viable population of humans is between 100 and 200 people. The technically difficult parts of the program will be designing and constructing a closed-loop life-support system to keep them alive, the task of taking an asteroid and turning it into a colony, and developing enough heavy lift capability to get everything you need up into space to get the colony established. The most difficult part of the program will be to keep the program from being killed by the political infighting and/or sabotage.

[CaptainChewbacca]

The minimum size for an ideal genetic pool for a human group is 30 mating pairs, though if you had to fudge it you could cut the number of men in half and just make sure they father children with at least 3 different women.

[Junghalli]

And even if it probably won't work, we don't have any better options, so what's the harm in trying?

[Lord MJ]

How long would it take for the common man to know about the Asteroid if the Government decided to cover it up? When would such an Asteroid be visible to the naked eye?

[CaptainChewbacca]

How long would it take for the common man to know about the Asteroid if the Government decided to cover it up? When would such an Asteroid be visible to the naked eye?

It depends on where it's coming from. If it is at an odd angle, or can only be seen from the southern hemisphere, fewer people are likely to see it. Likewise, if it is coming from behind the sun it will be hard to see. As for visible to the naked eye, that depends on a lot of variables, including ice content and surface albedo. We've had asteroids make near-misses of earth that we had less than a week's notice, so in this scenario you can get as much or as little warning as you want.

[GrandMasterTerwynn]

How long would it take for the common man to know about the Asteroid if the Government decided to cover it up? When would such an Asteroid be visible to the naked eye?

At T-50 years, the asteroid would be several tens of billions of kilometers from Earth. It's twice Pluto's diameter, so there'd be a ripple of news stories about the discovery of the biggest KBO to date. To cover it up would require a global conspiracy strong enough to haunt the nightmares of even the most intrepid tin-foil fruitcake. The moment scientists agreed that its orbit would result in the conversion of Earth into a belt of asteroids, the news would probably be all over the Internet.

If we use a 3000 mile diameter as a good ballpark, our putative asteroid is almost 94% the diameter of Jupiter's moon Ganymede. If it weren't for Jupiter, the Galilean moons would all be naked-eye visible from even a modest dark-sky site. The furthest Jupiter is from Earth is nearly a billion kilometers. So the asteroid becomes naked-eye visible by around T-8 months. Of course, this assumes our putative asteroid has a surface covered in a lot of ice and soil, so its initial surface brightness would be as high as Ganymede's. If it was only as intrinsically bright as Mars, basic naked-eye visibility would be established by T-3 months instead, and would be visible from the heart of cities a month or so later.

[Erik von Nein]

Any self-sustain colony is going to have to get over the rather massive hurdle of how they're going to produce enough nutrients to properly take care of any sizable population. How they're going to produce enough of the right vitamins, minerals, fats, carbohydrates, and proteins to sustain a colony of over 1000 within 50 years.

EDIT: Never mind figuring out a way to expand said facilities with nearly all manufacturing being blown to Hell and back. That's a lot of rare earth metals and machinery you aren't getting back.

[Knife]

Any self-sustain colony is going to have to get over the rather massive hurdle of how they're going to produce enough nutrients to properly take care of any sizable population. How they're going to produce enough of the right vitamins, minerals, fats, carbohydrates, and proteins to sustain a colony of over 1000 within 50 years.

EDIT: Never mind figuring out a way to expand said facilities with nearly all manufacturing being blown to Hell and back. That's a lot of rare earth metals and machinery you aren't getting back.

At a minimum anyways. Not RDA of vitamins and minerals, we're talking bare minimum expecting some to die from scurvy.

Anyway, I'd be more in line with trying to divert it rather than last ditch chance to send humanity out into space to outlive it.

[Erik von Nein]

If you can't provide a proper amount of Vit C they're going to be dying of a lot more than just scurvy. Especially if they start having children.

[GrandMasterTerwynn]

Any self-sustain colony is going to have to get over the rather massive hurdle of how they're going to produce enough nutrients to properly take care of any sizable population. How they're going to produce enough of the right vitamins, minerals, fats, carbohydrates, and proteins to sustain a colony of over 1000 within 50 years.

EDIT: Never mind figuring out a way to expand said facilities with nearly all manufacturing being blown to Hell and back. That's a lot of rare earth metals and machinery you aren't getting back.

At a minimum anyways. Not RDA of vitamins and minerals, we're talking bare minimum expecting some to die from scurvy.

Anyway, I'd be more in line with trying to divert it rather than last ditch chance to send humanity out into space to outlive it.

Given the size ballpark of the incoming asteroid, it'd be like trying to move the planet Mercury. You'd have to induce a significant orbital deflection too. At least a couple of Earth diameters, and even then, you'll kill most of the coastal populations with the tides raised. With present technology, it is absolutely impossible in the timeframe given. Sure, if we could magically get there while it was still 50 years out, we'd 'only' need to impart a mega-newton of thrust (assuming it were made of ice. Over 9 mega-newtons if it were a solid hunk of nickel-iron) in a direction tangential to its collision course of Earth. Sure that's like 1/32nd the thrust of the SSTS stack, but it'd have to operate continuously for the next fifty years.

In this scenario, trying to build a self-sustaining space colony would be the easiest approach. Well, apart from the "bend over and kiss our asses goodbye" tactic.

[Dark Flame]

Okay, I don't know much about this, so please bear with me.

I believe someone earlier said that the asteroid is spinning. Why? Do all asteroids do this?

If we use thermonuclear bombs, what are the goals? Are we trying to break it into small chunks? Use the force of the explosion to knock it off course?

Is the goal to knock off enough iron/rock/whatever to alter the center of gravity so that when it spins it will spin itself off course? Is that a viable idea? Is that what you were alluding to all along?

[The Vortex Empire]

Diverting an asteroid the size of the US? With our technology? Not a chance. Our only hope would be to try to make a small settlement on Mars. I don't know whether we have the capability to settle Mars and build a self sustaining base on it, but I suspect we don't. Nothing on Earth will survive, that much you can be sure of.

[Guardsman Bass]

Given the size ballpark of the incoming asteroid, it'd be like trying to move the planet Mercury. You'd have to induce a significant orbital deflection too. At least a couple of Earth diameters, and even then, you'll kill most of the coastal populations with the tides raised. With present technology, it is absolutely impossible in the timeframe given. Sure, if we could magically get there while it was still 50 years out, we'd 'only' need to impart a mega-newton of thrust (assuming it were made of ice. Over 9 mega-newtons if it were a solid hunk of nickel-iron) in a direction tangential to its collision course of Earth. Sure that's like 1/32nd the thrust of the SSTS stack, but it'd have to operate continuously for the next fifty years.

Wouldn't that depend on the path it's taking? I was wondering if you could just push it a little bit closer to the Outer System Gas Giants, then see if their gravity fucks with its trajectory a bit (although I wouldn't exactly want a planet of that size to fall into Jupiter).

Incidently, something like this was happening in one of Arthur C. Clarke's later novels, The Light of Other Days (although that's not what the story was mainly about). They had a giant piece of rock about 400 miles across that was projected to impact around 2650 C.E. (it was in the 2040s or 50s in the novel). Of course, you could probably do a lot more with six centuries rather than 50 years . . .

[Lord MJ]

Since the consensus is that indeed we are screwed, lets focus on the how it would effect your personal life if you knew in 50 years Earth would end, societal impacts, geopolitical impacts?

[The Romulan Republic]

Yeah, set up a moon colony. Good plan. Then what? Even if they survive the initial impact it's not like they're going to have any kind of support. They won't be able to live there indefinitely.

Christ, not on the Moon. Probably the Moon's biggest edge on Mars is that its easier to get to. Mars in terms of resources and environment is a superior world for a permanent base that has to be pretty much completely self-sufficient.

I would say try to divert it (might as well try), and in the meantime begin aggressively funding a Mars program with a goal of setting up a self-sufficient colony. At least we have half a century's time to do it, and cost is not an issue when we're talking about species survival. However, it might be hard to justify the spending without going public with it, and I can see the government being reluctant to do that (actually if nothing else the deflection efforts could help calm panic by convincing people that the government wasn't just writing them off).

[Alyeska]

In order to stave off panic the government is going to need to run multiple programs. Mars will have to be billed as worst case even if its the most likely. Fallout shelters will have to be built (there is a remote chance human life could survive, at least a while). And an asteroid deflection program must be funded to keep the public optimistic. If we are to reach Mars, we need the people to have a will to live. The worlds governments are going to need to control their media very tightly in order to try and maintain public moral. I hate to say it, but marshal law might be required.

[Stark]

Since the consensus is that indeed we are screwed, lets focus on the how it would effect your personal life if you knew in 50 years Earth would end, societal impacts, geopolitical impacts?

To be honest I'm not sure I'd care. Deflection is impossible and escape is probably impossible and the chance of me personally being involve is vanishingly small, so I'm basically going to die in 50 years. The hubbub as people desperately try to escape/save the world would probably make it a truly annoying 50 years however; particularly since survivalists will probably go apeshit in their need to secure a future and stomp all over rights, economy, etc. Instead of 50 years of normality with a full stop at the end, I'd expect 50 years of near-chaos with a full stop at the end.

[The Romulan Republic]

Any self-sustain colony is going to have to get over the rather massive hurdle of how they're going to produce enough nutrients to properly take care of any sizable population. How they're going to produce enough of the right vitamins, minerals, fats, carbohydrates, and proteins to sustain a colony of over 1000 within 50 years.

We don't need a thousand for a viable breeding population, though given the shear number of jobs needed to keep an industrialized society running, I suppose we want as many as we can get.

However, you can grow plants on Mars, or in an asteroid colony (not on the Moon though, at least not with natural light, given the month-long day).

EDIT: Never mind figuring out a way to expand said facilities with nearly all manufacturing being blown to Hell and back. That's a lot of rare earth metals and machinery you aren't getting back.

No idea about this. I'm pretty sure a lot of the metals can be found on Mars or in the asteroids, but replacing the heavy manufacturing on Earth? No idea.

[Knife]

Honestly, besides a good run, I'll be dead in 50 years so that fact will effect me less than how that effect will...effect people younger than me. Will the world go to shit if young people will die horribly when they are old? Pretty much the question.

[Junghalli]

Sure, if we could magically get there while it was still 50 years out, we'd 'only' need to impart a mega-newton of thrust (assuming it were made of ice. Over 9 mega-newtons if it were a solid hunk of nickel-iron) in a direction tangential to its collision course of Earth. Sure that's like 1/32nd the thrust of the SSTS stack, but it'd have to operate continuously for the next fifty years.

Hmm, my gut instinct said it'd take a lot more energy than that. Hmm, this might give us some sort of hope. We'd need to send up a massive Orion (the huge "super-Orion" designs should do) loaded with a bunch of mass drivers and a nuclear reactor or three and send them to the planet. Over there we set up a small self-sufficient base, manned by a small crew of volunteers, who set up the mass drivers pointing straight up in the appropriate spot and start shoveling rocks into them. You'll definitely need the base, for maintenance over the necessary decades, and you'll want multiple mass drivers so they can be shut down and rotated for maintenance every once in a while (I doubt you'll be able to achieve the necessary thrust with one mass driver anyway). Maybe send out smaller follow-up missions to deliver new ones every five or ten years.

The biggest problem will be the planet will probably be rotating, so the mass drivers will only be aligned correctly for a short window. You'd need massive overcapacity to make up for this (2 billion newtons, say).

It'd be a long shot and cringe-inducingly expensive, but we've certainly got every incentive to pour money on it like there's no tomorrow. I could see us attempting something like this even if it probably won't work, just to stave away the social chaos by giving people hope while they go about the real salvation project (second Orion send to Mars establish a small self-sufficient colony).

[CaptainChewbacca]

I was going to suggest mass-drivers as the most likely way to deflect the thing. If we've got fifty years to work with, we should be able to get a diversion program assembled and launched in 10. Nuclear pulse, and maybe its another 2 or 3 years to the asteroid. That gives us over 30 years to work on trying to alter the asteroid's trajectory. For our civilization to survive, we need to divert this thing by at least 100,000 miles, at which point it will only be the biggest disaster in human history (tides, earthquakes, volcanoes, etc). It might put us into a new dark age, but we'll survive.

[Sarevok]

Why off world ? If you can survive on a place as harsh as the moon you can live as well on Earth. The main problem would be surviving the impact. But this could be solved by same means as off world colonization but at fraction of the cost. Just launch people and any hardware too fragile to survive into orbit prior to the impact, then after when the shockwave passes they simply land back on the surface. This is a lot more cheaper than sending a full fledged colony expedition to Mars.

[Alyeska]

The impact is going to cause significant damage to a great deal of whatever remains in Earth orbit.

[Junghalli]

Why off world ? If you can survive on a place as harsh as the moon you can live as well on Earth.

Because the impact will melt much of the crust. Even the moon is more survivable than lava-world. Even if you're on the opposite side of the planet, the seismic effects will probably destroy any bunkers.