Premise: The world is going to end in ten years(the reason for the benefit of this exercise doesn’t really matter), and the governments decide to work together to build a generational ship in those ten years. This leaves just about no time to fiddle with inventing new technologies-we have to start building NOW! Can we do it? How many people do we send, and in how large a ship? Using current technology how long will the trip take, and in which direction do we point the ship?
10 years? We have no chance…might as well just resign ourselves to the inevitable. I don’t think we could plan and achieve a significant colony on Mars in that time frame, let alone design, develop and build an interstellar space ship to transport a significant human colony to save the species. Maybe 100 years, but not 10.
As to brute force tech we could use off the shelf today, I’d say the only viable option would be Orion. I don’t think NASA’s in development fission/fusion drive is anywhere near ready today for actual use…certainly not in that time frame.
Yeah, then no chance is my vote. There is literally nothing we could do in 10 years to save even a seed of our (or any other) species in that time frame. Even if they had to merely leave in 10 years to avoid whatever, it’s not possible IMHO.
Might as well name it the Titanic. Or maybe the Flying Dutchman.
Using today’s technology? We couldn’t shield it against interstellar radiation. Everything aboard dies horribly, and it wanders, ghostlike, forever in the void.
Seriously, no. We couldn’t even build the puppy. What engines? What fuel? What supplies? Thousands of years to get to the nearest star…and the Alpha Centauri complex probably doesn’t have habitable planets.
When you say “the governments decide to work together,” are you eliminating social issues from the scenario? Because if you don’t eliminate those, I think the entire thing will be bogged down in the bucket-of-crabs scenario: we poor crabs who have to stay in earth’s gravity well will pull back anyone who’s going to get to survive. There’ll be massive civil unrest the likes of which has never been seen before. How many people are going to be willing to devote all their energies to this project knowing that their babies won’t live to see their eighteenth birthday?
But if you eliminate those social pressures–if, say, inscrutable aliens promise to avert the disaster if all earth bands together to create a working generational ship–then it goes from the totally impossible to the merely unlikely. The odds against it are
Edit: one possible way to band people together would be the lottery: every month you spend employed by the Generational Spaceship Project earns you one lottery ticket for a seat aboard the spaceship. Nobody can win more than one seat, but if you win, you’re allowed to transfer your ticket one time (so, no ticket-brokers buying them up). That’s not going to be a perfect solution, but it might eliminate a fair amount of unrest and get more people to sign on.
My WAG would be a minimum of 50 years to get things organized, research the technology and build the thing and get it flying and outward bound. You’d probably want to find a better destination than PC as well, since AFAIK there aren’t any really good candidates for habitable planets there. I’d say in 50 years, with the proper draconian measures taken, the combined nations of Earth could design and produce a space ship capable of taking a viable human population (with at least some other species, especially plant species along as well) with at least a small chance of success. Would be pretty long odds even then, but I guess a 1 in 100 chance is better than no chance at all. 10 years though? No way.
Simply wrap the habitable parts of the ship in a water jacket and waste recycling system should do the trick. You could also put all of the materials and other supplies you’d need in the outer hull to act as further shielding. If you had more time, you could build a more active radiation system (maybe a plasma or magnetic field of some kind), but I think the water for the mission alone, along with waste generated and needing recycling should be enough to protect the crew by and large.
People always tend to forget the “generation” part when they talk about building a ship like this.
Tell you what. Build yourself a sealed biosphere on Baffin Island. Once it’s sealed you’re not allowed to use outside air, or food, or water, or sunlight, or fuel, or libraries, or internet, or medicine. Cram a bunch of people into it. No one goes in, no one goes out.
How long do you think it will take until the last human being inside the biosphere is dead? 5 years? 10 years? Remember you can’t use sunlight to grow plants, you’ve got to use your internal power plant to generate electricity to power lamps to grow food.
Now, instead of building on Baffin Island, you’ve got to build this biosphere in orbit, which makes it 1000 times more expensive and difficult. How are you going to accomplish this? Yeah, yeah, asteroid mining. That’s fine, except you’ve got to, you know, invent asteroid mining first.
Now imagine that you’ve also got to strap giant rocket engines on this orbital biosphere and head for Alpha Centauri.
What’s my budget? What’s the incentive of the people trapped in there to be in there? Give me the resources of the world and highly motivated people and I don’t see why you couldn’t have the people live indefinitely in a close habitat.
Build another Voyager and put a bunch of freeze-dried bacteria on board along with all of Earth’s stored knowledge including a complete map of the human genome. In only a million years or so it may crash-land somewhere that will allow the bacteria to begin evolving into a sapient lifeform that will eventually be capable of accessing the stored knowledge and gene-splice a human from scratch using the supplied genome information.
It’s a long shot with a lot of built-in delay, but it’s far more likely to succeed than any attempt to build a generation ship that has a hope in hell of making it to a habitable planet in another solar system. We don’t have the first idea whether a Centauri has one nor any realistic means of finding one in the next ten years even if we could build a ship that would keep a human colony alive long enough to reach it. You might as well swallow your pride and pray.
But this biosphere is something that’s never been done before. Look at the trouble the Biosphere II people ran into, and they were getting free sunlight, plus a shipment of oxygen, plus medical care when someone sliced their hand open.
Let’s say you’re going to cram 100 people into this biosphere. How much underground acreage do you have to devote to hydroponic crops, powered by lights from the nuclear reactor? And if anything goes wrong, everyone dies choking. Nobody is going to starve to death, because if the hydroponics fail and you have no food for next week you’re going to miss the oxygen first.
We don’t appreciate the sheer amount of life support we get for free, living on a planet where oxygen is created by trillions of plants, water falls from the sky, and sunlight is turned into food and building materials.
True enough, but then they didn’t exactly have a huge budget. IIRC it was a hundred million or so spread out over nearly a decade. Give me a budget of a few hundred billion or the odd trillion or so and I can guarantee that the folks inside will live. The fact that something has never been done doesn’t mean it can’t be, and with the motivation of the end of the species I’m thinking folks will figure something out…or, as the saying goes, die trying.
So, you build in large redundancies into the system. If you think you need one reactor, you put in 4, plus all the spare parts and machine tools to repair them several times over. If you think you can recycle 75% of the water then you build in a 150% reserve. If you think you can sustain hydroponics you put in a large emergency supply of food AND the equipment to completely replace the hydroponics several times over, with plenty of seed crops in case of failure. Same goes for every other vital and even non-vital component. Again, instead of spending a couple of hundred million dollars (which sounds like a lot, but really isn’t much) you spend a couple hundred billion on your Biosphere III, if you really, REALLY want it to succeed.
Same goes for this generation ship. You put in redundancies on top of redundancies…hell, you build two that will travel in company, or 3 or 4. With auxiliary or supply ships to fly with them. You spend trillions…the resources of the entire world. Why not, since everyone is going to die anyway, right?
Certainly, but we do have experience in space, and if you and I can envision the issues, think about all the resources and brain power of the entire world. The tricky part would be the political aspects, I’m thinking…the rest is just resources and engineering. It COULD be done. Might only have a 1 in 100 shot of success, or maybe even one in a thousand or one in a million…but it’s better odds than zero.