How far are we from colonizing off Earth?

[Pbartender]

Yup.


80000/100 = 800 years. I hope the theoretical max of those is a lot better.

By the way, there is something theoretical that is actually faster than the Orion. Remember the cool ship at the beginning of Avatar? That's actually based on the Valkyrie antimatter propulsion model. It could get you to 92% lightspeed. Guess what the downside is? Antimatter is expensive enough to bankrupt the entire planet several times over.

It's not the cost of antimatter that's prohibitive, but the time it takes to produce it in any quantity and the ability to effectively store it for any length of time.

The last time I checked, our best antimatter "factory" can't produce much more than about a billionth of a spoonful of antimatter in a year, and it doesn't even have the capacity store all of that at once, much less ship it anywhere useful. The storage facility -- for round about a hundred-billionth of a gram, mind you -- is a ring a half kilometer in circumference and made of electromagnets the size of small cars.

Considering that a typical one-month trip to Mars would require roughly 10 grams or so (a third of an ounce) of antimatter, I don't think antimatter propulsion will viable any time in the near future without some truly amazing breakthroughs in high-energy physics technology. It hard to say how soon it could happen, but I wouldn't bet money on it.

 

[jonesy]

The storage facility -- for round about a hundred-billionth of a gram, mind you -- is a ring a half kilometer in circumference and made of electromagnets the size of small cars.

Yikes. Does that scale accordingly? If you need a bigger lump of the stuff, do you also need a bigger ring and magnets?

 

[coyote6]

Charles Stross has had some interesting blog posts on this subject; here's one. He does not seem to think it's terrifically feasible, barring some impossible-to-predict technological inventions. He points out the many areas of Earth that are uninhabited, yet far more inhabitable than Mars or the like.

 

[catsclaw227]

According to Stephen Hawking, in a recent article on Kurzweilai.net, we best be getting out butts moving on this otherwise we'll just burn out the planet we are on.

Stephen Hawking’s Warning: Abandon Earth—Or Face Extinction | KurzweilAI

 

[Pbartender]

According to Stephen Hawking, in a recent article on Kurzweilai.net, we best be getting out butts moving on this otherwise we'll just burn out the planet we are on.

Stephen Hawking’s Warning: Abandon Earth—Or Face Extinction | KurzweilAI

As smart as he is, there's a fundamental flaw in Hawking's argument, however...

As Coyote6 says, barring some impossible-to-predict technological inventions, there's no way that extraterrestrial colonization is going to make the slightest dent in either our population problem or our resource consumption problem. We just can't feasibly ship people out fast enough, and we can't ship resources in fast enough to make any appreciable difference.

All we could hope for is to establish a sort of off-world "Noah's Ark" so that human society and earth ecology can continue should some catastrophe befall Earth... At best, it'd prevent all of our eggs from sitting in one planetary basket.

And that is one of the main arguments against extraterrestrial colonization... That the resources, manpower and money for manned space exploration and colonization would be far better spent putting our own proverbial house in order, instead of moving into a new one and trashing that one too.

 

[TwinBahamut]

All told, there are just two things we need to done in order to put people anywhere in the solar system. First, we need a better way to put people and equipment into space than the traditional space shuttle system. Second, we need to put enough people and equipment into space in order to build a large permanent habitat in space capable of housing a few thousand people, processing materials, and manufacturing goods on its own. Once we have that, the solar system would be our playground.

With a single working orbital colony, strip-mining the moon for raw materials is ridiculously efficient compared to hauling stuff up from the Earth, so it becomes easy to build bigger and better orbital colonies. And once you have permanent space habitats, taking the long, energy efficient route to other planets in the solar system is a lot more feasible (certainly more feasible than launching a ship built on Earth directly to Mars), because even if it takes years to get anywhere you could still do so comfortably (and bring the whole family along for the ride). The first colonization of Mars probably won't be a couple dozen astronauts riding a shuttle launched from Earth's surface, it will probably be when a few large-scale permanent space colonies each filled with millions of people arrive into orbit around the planet.

Anyways, according to the people who first really looked into these possibilities, we could have had that critical, first permanent orbital colony by the mid nineties or so. So the question is not so much "How far are they away?" but rather "For what reasons have we not done so already?"

As for travel to worlds outside of the solar system... Honestly, I don't have a clue. I don't think identification of habitable Earth-like planets is at all necessary, since man-made structures placed near large gas-giants or in stable orbits of stars themselves would be perfectly suitable for human habitation. Nor do I think it would be strictly necessary to bring significant sub-light speeds into the equation, since people may very well be willing to set out on journeys that would not be completed in their own lifetimes. It probably won't happen until the solar system as whole becomes crowded, though, which may take centuries or even millenia from the time the colonization of the solar system begins.

 

[Banshee16]

60 million lightyears? There must be a unit conversion error there somewhere. I'm just having trouble deciding which one it might be.

Erk.....just a tad.....that should have said 60 light years....but I think while writing it I was thinking it may as well take 60 million years to get there, at current speeds.

But with the distances involved it hardly matters.

The closest star is Proxima Centauri at 4.2 lightyears. That's about 40 trillion kilometers.

The closest detected exoplanet (planet orbiting a star other than Sol) orbits Epsilon Eridani, which is 10.5 lightyears away (63 trillion miles). Most of the others (that we've detected) are within 300 lightyears of us.

What's 60 million lightyears away? the spiral galaxy called Messier 90.

I didn't think we had stars that "close" to us. I thought they were much further out. In any case, do we really *know* that no stars closer than 300 light years away have planets? Or have we just not seen them yet? As far as I know, it's only in the last 10-20 years that we've been starting to actually, definitely "see" planets around other stars. My understanding is that even with the best telescopes, we don't "see" planets around other stars...we mainly get guestimate that they're there, based on seeing refracted light that tells of the presence of certain gases or minerals that indicate planets, or calculate based on analyzing gravitational movements of other stars, which indicate planetary bodies are circling them.

I'd guess that there are a lot more planets out there, even in our close neighbourhood, and it's just that our instrumentation isn't powerful enough to detect it yet. Plus, budgets applied to finding planets etc. are still limited, hence we might be able to find more planets closer, sooner, if we were able to throw more money into detecting them.

Similar to how budgetary limitations mean that we're really blind to how many space rocks with civilization or nation-ending potential are out there, on possible collision courses.

The fastest theoretically viable stardrive at the moment seems to be nuclear pulse propulsion (correct me if you find something faster, please). The Project Orion. It would get you to Proxima Centauri in 85 years. If you used the Ion drive we now have working, 8000 years. Yeah.

Edit: sorry, now I made an error: the ion drive would get you to Proxima Centauri in 80000 years.

So, again, barring some kind of technical discovery, such as figuring out that wormholes exist in anything besides the theoretical, and then actually using them to move vast distances instantly, we don't have any conclusive way to move to these other star systems in any approximation of feasible time periods. I mean, Michael Crichton did it in "Sphere", but who knows if that will ever happen?

I'm not sure we'll ever get nuclear drives working for space travel. And even if we did have a craft capable of going 90% of the speed of light, and as a result, we get to a star that is 4.2 light years away in 4.6 years.......isn't there a dilation effect whereby people left behind on earth will have experienced a longer period of time? Or is that not correct? If it *is* correct, how much time would have passed on earth while they were traveling to the next star?

Of course you never know. Science is progressing rapidly in a lot of fields. I had read that cryogenic suspension was basically science fiction....because when they try to "thaw" subjects after suspending them the cells rupture, and they die (when working with cells in the lab, not with human test subjects). But I've also read that in the last 2-3 years, they've been making strides, and they're talking about experimenting with extreme cold used to slow or suspend physiological activity in accident victims, in order to improve survival rates in trauma victims. The article had commented that most trauma victims who die, die because they bleed out before the doctors can fix the damage. So if they can slow down the body's systems so that doctors can repair the damage, the person could be brought back once the damage is repaired.

And if they can do that, it would likely be a big step in the right direction to some kind of cryogenic suspension, you would think.

As to whether to colonize other planets or not. As a matter of species survival it makes sense, if possible. All it would take is one bad day encountering a space rock, and that's it for homo sapiens. Heck, we could have a day that's bad enough to maybe not kill everyone, but eliminate 99% of the global population, and send us back to the stone age.

Haven't astronomers said something about human civilization having evolved during a period when our solar system was passing through a part of the galaxy where there was a relatively low level of space clutter, but we're moving back into the busier areas? Obviously solar systems move very slowly.....but the technological, practical, and financial advances to get us to other planets are so significant, what is the likelihood we get anywhere before we get hit by something big?

And if it's not that, global climate change could make things unpleasant, we could run out of certain needed materials/supplies, have a global nuclear conflict, or run into the next ice age. Any of those things could put us in a position where we have no resources to devote to space travel.

Banshee

 

[Banshee16]

Yep. Probably ion engines run off a small nuclear power plant.



Um, no. The entire galaxy is only 100,000 light years in diameter. The nearest star is 4.37 light years (about 26 trillion miles) away



If we can get a craft up to 10% of lightspeed, it'd take about 60 or 70 years to reach the nearest star. The nearest known planet outside the solar system is somewhat more distant (about 10 light years away).

60 to 70 years to reach another star. That's an immense amount of time. I don't think it's even practical to contemplate. You basically either need to have one of two things (IMO):

A) Super-developed AI's, in combination with workable cryogenic technology allowing you to freeze your crew, and only bring them out in moments of crisis, or when you are almost at your destination.

or

B) A super huge ship with a large population, more than we've ever put into space before. 60 or 70 years? Assuming that your astronauts are 20 years old when they launch, they're going to be 80 or 90 years old when they get there. So either you've got astronauts who have enough life in them to push some buttons and make sure to be able to send a message back to say "yeah", there's a good planet here, send the next ship...with that message getting home in how many years after that? Or you have to have that ship with a huge population, so that you can support astronauts having babies in space, with all the medical complications and supply issues that entails...because it's going to be 3 generations after liftoff that you finally get where you're going.

To me it just doesn't seem realistic. I don't think it means we don't look for solutions...I just kind of think that getting to another solar system is more science fiction fantasy than anything else. Look how much human civilization has changed in 70 years. How can you stick astronauts on a ship to another solar system, and have them arrive 70 years later, sane, unless basically what you're sending is a colony ship of sorts?

Banshee

 

[Pbartender]

Yikes. Does that scale accordingly? If you need a bigger lump of the stuff, do you also need a bigger ring and magnets?

It depends on what your goal with the antimatter is...

The circumference of the ring is determined by the energy of the particles you are containing. If they're more energetic (in general, and before relativity takes too much effect, moving "faster"), you need need either a larger circumference or more powerful dipole magnets to keep them turning the circle. Think of it like a race track... Really fast cars need a very gradual turn or a very steep embankment to keep from flying off the road when they turn. Of course at the aforementioned Fermilab, energy is important, since the antiprotons are being used for collider experiments. Higher energy == better experimental results. When storing for propulsion purposes, the "speed" of the particles is less of a concern, so it's likely a storage ring for such purposes could be of a much smaller diameter.

However, there's another problem... particles with similar charges repel each other. The antiprotons we use at Fermilab, for example, are all negatively charged, which is what allows us to use magnetic fields to store them by spinning them around in circles. Anyway, what this means is, when you have a group of like-charged particles hanging out, they tend to disperse since they all repel each other. That means you have to actively focus the beam using a host of tricks like quadrupole, sextupole and octupole magnets, and radio frequency stochastic cooling systems, and blah-blah-blah sounds like it's straight out of a Star Trek episode.

That's what's holding us up. The more you store, the harder it is to hold it in. Our current technology isn't good enough to make and store much more than a speck, and while advances are being made, it's not a high enough priority to spend the sort of time and money on it that we'd need to in order to turn it into propulsion.

It's not like in Angels and Demons where you can just hold enough antimatter to blow up a small city in a glass jar the size of a two liter bottle of soda powered by nothing but a couple of rechargeable D-cell batteries and carry it around with you.

 

[Orius]

Right now, it looks like the leading impetus for any type of colonization on the moon might be commercial tourism. As for official research and exploration type colonization, it seems to be on permanent high-speed hold. Until the world's economies significantly improve, I just don't see it happening.

Yeah, space tourism is likely to be the main impetus in the near future, the super-rich have run out of places to see here on Earth so the need to go into space to brag about something.

A lot of the problem is politics and a lack of vision to go into space. Exploration in the past was carried out partially because expanding empires were looking to conquer new territory. But there's a view in many of the nations who currently have any space flight capabilities that the whole nation-state concept is outdated and shouild be discarded, and that the whole space race was just a bunch of worthless patriotic chest-thumping that did nothing but plant a flag on the moon and bring back some rocks and dirt, and thus was a colossal waste of money, we should take care of our own problems instead. Never mind that one such problem that is nearly always brought up is poverty, which we haven't gotten around to solving in 6 odd millenia of recorded civilization. If we could solve it in that much time is it worth the effort, or do our thinkers and moral authorities think they can do so because some of their ethics are different from those of the past? My problem with that is if you look for excuses not to go into space, you'll never develop any of the needed technologies or propulsion to do so.

At least some nations aren't so blinded by such thinking. We'll need it eventually, because I agree with Hawking's assessment; staying stuck on Earth indefinitely will lead to our eventual extinction. Even if we don't wipe ourselves out, the world cannot sustain us forever, even it can do so for a million lifetimes. And we're not just a herd of stupid animals acting on instinctive impulses to feed and mate (well sometimes we aren't), we're aware of our existance and the likely potential for our own eventual extinction. Some people have children because they know someday they will die, and they hope they can raise their children to influence the next generation. Trying to get offworld does this for the whole human race, getting offworld is the only way we can ensure the survival of humanity over the very long term. The only extinction of H. sapiens I am willing to accept is one that happens after a new species of Homo has emerged and carries on our legacy. Anything else to me is absolutely morally unacceptable.