Author Topic: Reflections on the colonization of other planetary systems  (Read 10064 times)

Offline Rabit

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The main problem of distance * (ie, the time it takes to reach your destination) and the cost of sending anything outside the solar system.

Theoretical drives to allow passage between the stars:
Max speed includind acelerationa and deacleration
Pulse nuclear drive              2-2.5% C theoretically available
Pulse thermo-nuclear drive  4-5% C theoretically available
Fusion drive                         4-5% C Probably available in a few decades
Antimatter Drive                  20-40% C Lack of fuel

To colony has not genetic degradation due to the small gene pool need min theoretically 7,000 individuals, + buffer contingency 1-3 thousand.

So you need to send 10,000 people, even if we assume that we have the technology hibernation. It's on every colonist would have to accept from 500 kg to 1 000 kg weight * (capsule + hardware capable of running for at least 100 years).

So the colonists themselves were taken from 5-10 thousand tons of cargo.

This would require huge ship, as well as huge amounts of funding.

But if we reject the need for transporting colonists, and we create them on the spot trouble building such large ships disappear, and instead of one, we can for the same price to send tens.

So send an unmanned ship equipped with:
1 computer with stored digitally coda genetic colonists eg 1-5 million.
2 module processing and production * (minimum weight using Nanorobotics)
3 nuclear reactor power system MSR or fusion reactor.
4 drive one of the abovementioned
5 Layout of sensors / probes that allow the system to locate a suitable target asteroid.

So the ship after reaching the target. Looking asteroid that will provide him the required resources to build: habitat, industrial facilities, additional vessels from other mining asteroids, etc.

After the construction of the above and the gathering of resources.
Construction begins the synthesis of organic substances, and then generates synthetic womb and placed it in them to synthesize human embryos * (If there were no technology to their synthesis need to take them with you or take sperm and eggs).
When so conceived people came to the world are waiting to them androids * (resp. humanoid robots), or they would have been connecting to the VR to pass education.

After the achievement of the target population by computer colonies colonists gave to the authorities. * (Do not have to SI, because we are dealing with an artificial environment, where a limited number of possibilities, otherwise would have been if the computer had to assume a colony on the planet's surface).

In addition after creation of the colony ship can resupply fuel, and go for antother star system for colonization * (only fusion drive).

Possibly required for the idea technologies in the field of nanotechnology and biotechnology are at the moment not available.
« Last Edit: 06/20/2014 01:18 PM by Rabit »

Offline Stormbringer

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new calculations based on optimized magnetic nozzle design basically double the maximum speed available to antimatter and various other propulsion schemes that use magnetic nozzles.also the max theoretical speed for fusion is about 20 percent c (assuming a steady fusion burn instead of pulses or intermittent) so if the new model applies that would turn into 40 percent c. there are outlier antimatter designs that could reach..92 c. the design is radical and involves a beamed core engine and a kilometers long tether to tow the crew and cargo. this eliminate a huge amount of the inert mass of a conventional design that would normally be for a rigid structure and hull or shell and reduces the mass of the shadow shield.
« Last Edit: 06/20/2014 05:26 PM by Stormbringer »
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Offline Vultur

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There's no way you need 10,000 people starting populations for genetic reasons. All Native Americans may come from ~100 people founder population. Pitcairn Island is less. Pingelap was 20 people and the only real effect was an increased chance of colorblindness, they didn't end up with any really serious health problems.

Human genetic diversity is actually quite small to start with compared with other widespread species (though not to the degree of cheetahs).

Also, I am really ultra skeptical of AI/robots capable of raising human beings who are halfway sane.

Furthermore, making the ship small may not be the best bet given interstellar dust impacts. You will probably need really significant (and heavy) protection. At 1% c an object has kinetic energy of about 1 million times its own mass in TNT -- a 1 microgram dust grain is the equivalent of a heavy bullet, several kilojoules. At 10% c it's a hundred times worse. And when you start getting near lightspeed relativistic effects make it REALLY heavy.

I think generation ships (or maybe not strictly generational, assuming sufficient life extension, but still huge whole-ecosystem 'worldships/interstellar arks') at 'low' interstellar speeds (say maybe 100 to 1000 years to Alpha Centauri or Barnard's Star) are the best bet. Build it tough, maybe with an asteroid made into really thick shielding, and use nuclear pulse propulsion.

If a civilization already has asteroid colonies or O'Neill colonies, moving to worldships/generation ships is a small leap... and there's not much point in going interstellar until the Solar System is fairly thoroughly colonized/industrialized.

Offline Hanelyp

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Assuming high genetic diversity is wanted, frozen eggs and sperm are a lot more mass efficient than a live colonist.

Vultur makes a good point about interstellar dust.  At even 1% light speed a small speck of dust carries a LOT of energy.

Offline scienceguy

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interstellar dust is charged. You can deflect it with a magnetic field.
e^(pi*i) = -1

Offline su27k

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You'll need an AI that is equivalent to human to bring up the children, but once you have an AI like that one wonders why do you need the meat bodies at all, except may be for sentimental reasons. I do agree these kind of seed ships are the most likely way of interstellar colonization, we're pouring huge amount of money into AI/biotech/nanotech research, and these technologies will likely mature well before any propulsion tech required for generation ships.

Offline Stormbringer

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interstellar dust is charged. You can deflect it with a magnetic field.

yes even up to slightly larger than sand grain sized can be deflected electrostatically/magnetically or captured into a molten metal curtain type radiator's working fluid. largerones impact exponetially less often. and they could be handled by something like a solid state laser/lidar combination or good ol' minute maneuvers from a great enough distance away.
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Offline Vultur

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Assuming high genetic diversity is wanted, frozen eggs and sperm are a lot more mass efficient than a live colonist.

Thing is, I think the population you'll need for "variety of skills" reasons will be more than big enough for genetic purposes.

I say think big, big, big. Use nuclear pulse propulsion; by this point we should have massive in-space industry so we can use huge nuclear explosions since it won't be launched from Earth. If this is a project done by an "O'Neill colony" society or colonized asteroid belt, then the psychology of living in a worldship won't really be any different from what they already do.

Asking how much it will cost would be way premature at this point, since we don't have any idea of what the economy will be like when we have a widely colonized Solar System.

I don't think tiny ships propelled by solar / laser beamed sails are very likely to survive. In the decades of even a pretty fast interstellar journey, there will be a lot of dust hits. How well does a super-lightly-built solar sail stand up to that? Now maybe it will be SO thin that the dust just punches through and makes a comparatively small hole, but... I dunno. I have a feeling it might act un-intuitively at that speed.

We don't need transhumanist technology or strong AI or Bussard ramjets. Nuclear pulse propulsion, massive in-space industry, and the ability to make long-term-stable (centuries plus) closed ecosystems is enough to reach the stars, IMO.


interstellar dust is charged. You can deflect it with a magnetic field.

OK, but wouldn't that require a lot of energy? Far more than needed to run a computer and maybe a little heater?  Could a tiny "solid-state" AI-plus-computerized-DNA-plus-nanobots-to-build-bodies-and-infrastructure solar sail probe generate that kind of energy continuously on a multi-decade mission with no solar power available? It seems like you'd need pretty significant fuel mass for whatever generator you're using. (And if you can store significant amounts of antimatter for these kinds of timelines, doing a manned interstellar mission is probably well within your reach.)

Also, are the big particles (sand grain size, say) charged enough relative to their mass to be practical to repel?

Also, given that you'll be traveling a very long way, there's the possibility of an occasional bigger particle -- a bit of an Oort cloud comet say -- too big to magnetically repel, too small to see in time to dodge. Fist-sized maybe, or head-sized.

I'd want my interstellar spacecraft to be able to stand up to say 1 kiloton-of-TNT-equivalent hits at least (that's ~1 kg at 1% of lightspeed, or ~10 g at 10% of lightspeed). Probably much more. Which means a huge ship with very thick shielding.

You'll need an AI that is equivalent to human to bring up the children, but once you have an AI like that one wonders why do you need the meat bodies at all, except may be for sentimental reasons. I do agree these kind of seed ships are the most likely way of interstellar colonization, we're pouring huge amount of money into AI/biotech/nanotech research, and these technologies will likely mature well before any propulsion tech required for generation ships.

Well, that's the question. I don't think the tech for generation ships is actually very far away -- we're just not really developing it now, or at least not putting any significant resources into it (there are those MSNW/Helion guys working on a form of nuclear pulse propulsion, IIRC).

I think Biosphere II's mistakes have given people the idea that closed ecological systems are a lot more difficult than they IMO will actually prove to be. And nuclear pulse propulsion mostly has political problems, it's something we could start developing tomorrow if the will existed.

The thing that is farthest away is the huge in-space industry. Building a generation ship on Earth wouldn't make sense due to having to haul that huge amount of mass out of the gravity well. And I don't think it would work well with launchable sized modules either.

I am extremely skeptical of strong AI appearing anytime in the foreseeable future (and also pretty convinced that it's a very bad idea for both ethical and practical reasons). It's also a mostly useless technology IMO.

Sure, you can send AI without people, but without people or even any kind of reasonable data link back to the people (due to the light speed lag) what's the point? Something like Curiosity is close enough to real time for people to follow it, experience it, etc.

Given the huge scale of interstellar missions, assuming we'll have asteroid or O'Neill colonies well established before anybody launches a probe to say, Alpha Centauri, I wouldn't be especially surprised to find the first interstellar mission being a generation ship colonization mission. By that point the nearer star systems, planets and so on, will be very well known from really big space telescopes, IMO.

Offline scienceguy

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According to Grun et al. (2005), dust particles have a mass ranging from 10^-9 to 10^-14 g, or 10^-12 to 10^-17 kg, and a charge ranging from 10^-15 C to 10^-17 C. If we want the radius of the dust particle’s path to be say 1000 m while we are flying by at 0.10 c, then the strength of the magnetic field we will need will be:

B = mv/qr = (10^-12 kg)(3 x 10^7 m/s)/(10^-15 C)(1000 m) = 3 x 10^7 T

To generate a 3 x 10^7 T field, we would need a loop of wire carrying a current of:

I = B2(pi)r/u = (3 x 10^7 T)(2)(3.14)(1000 m)/(10^-7 Tm/A) = 2 x 10^18 A which is basically impossible, even with superconducting wires.

So I guess it would take way too much energy to have a magnetic field strong enough to deflect the dust particles.

It would be different if we were going much slower.

Reference

Eberhard Grün, Ralf Srama, Harald Krüger, Sascha Kempf, Valeri Dikarev, Stefan Helfert, Georg Moragas-Klostermeyer (2005) 2002 Kuiper prize lecture: Dust astronomy. Icarus 174:1-14
e^(pi*i) = -1

Offline john smith 19

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The thread topic is about colonization so people (at some point in the process) are essential.

So lets review the basics.

Bigger ship --> bigger energy demand  E proportional to m
higher speed --> much bigger energy demand. E proportional to v^2
TRL's for technology
Fission 8 Well Nerva got to ground test.

Fusion  2-3?

Fusion 1? (Well the Sun works)

Closed cycle ECLSS over say 6 decades 1

Effects of non Earth g on long term development. 1. Yes we know we should be studying this but apparently no one cares.

Ability to detect an Earth sized planet with sufficient detail to know it won't kill them outright. 3?

Turing equivalent AI. Getting better in narrow sense but as far away as you can get from a human IMHO.

Artificial womb 1 Actually first developed in 1965 but stopped due to massive ethics debate in the late 60's

Suspended animation. NAIC project at putting people into a "torpid" state to cut down resource needs to Mars. Doubt this is going to cut the resource bill enough over the timescale needed.

I'm always reminded of Frank Herbert's short story "By the book" which does interstellar colanization by carrying the embryos of the colonists in the wombs of rabbits in a capsule.

So to do this either a) Commit a huge chunk of the worlds resources to 1 or more flights or b) Devise a "low impact" architecture that can run on a small percentage of the solar systems economic output (and I don't think anyone will do this seriously until the human race is multi planatary).

The simplest near term approach I can devise is probably too ruthless to be capable of being implemented.

I'm thinking of a pair of small asteroids with Orion drives. Internally each has mostly smaller chambers to protect it's contents from a single depressurization event. The core first generation crew is small and all are experienced parents. The bulk are pre teens. Most of both groups will be in hibernation. The rest of the time they will be maintenance and training, including potential planetary habitats. It's going to be generational but in a knowingly artificial environment. The key issue is genetic diversity so I anticipate that they will carry a large sperm and egg bank. I don't think anything more than 3 generations is viable. Earth reproductive technology has advanced to the stage where a women of 70 can bring a child to term, which I think sets an outside limit on range at the kind of sub light speeds available.

At the end of journey the population starts to rise and education focuses on building the whole infrastructure from the ground up from mineral identification to materials selection (wood for example is likely to be a very different prospect from Earth. Oil? Who knows).

Obviously the key items are a very large egg/sperm bank, a huge database and an equally divers seed bank, all multiply copied.

Personally I quite like solar sails but that's not going to move an asteroid about (and you're going to needs something solid for radiation protection over 60-100 years).  :(



"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.
So you're going to Mars to seek a better life. What does that mean to you? Always spot a fanbois by how they react to their idols failures.

Offline Tass

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Re: Reflections on the colonization of other planetary systems
« Reply #10 on: 06/23/2014 09:44 AM »
Once you have a solar system spanning civilization, a thousand to a million times larger than today, it should be relatively easy to send a colony of a million people or so towards another star.

Even if we assume no really new technology (no fusion, people are still people living lifespans of less than a hundred years.) After some time of slow exponential growth, we could have something like 10^15 people living in O'Neill style habitats, at 10^6 kg of mass per person this would take 10^21 kg of material, or a third of the mass in the asteroid belt.

People seem fond of Orion style propulsion, but I see no reason not to simply use nuclear-electric. If you are going to take thousands of years for the journey, then you don't need high thrust. With the abundant solar power in space fissionables should be a quite cheap and unnecessary byproduct of extracting iron, aluminium, etc for habitat construction.

A 10^12 kg, one million people habitat would represent a billionth of the civilization's assets, probably pocket money for high net worth individuals. (A single good idea can be worth a billion (a thousand lifetimes work) in the present day, if a lot of the world will pay you a dollar (five minutes work) for it, in the future if there are quadrillions benefiting from the idea rather than billions, then it will be worth billions of lifetimes.)

All it would take to send a gaiaspore to another star, would be for the 24th centurys Elon Musk or Jeff Bezos to buy a habitat, fit it with ion motors and nuclear reactors to run them and to replace sunlight with artificial light, buy a bunch of uranium, thorium or plutonium, and send a million volunteers on their way.

Offline KelvinZero

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Re: Reflections on the colonization of other planetary systems
« Reply #11 on: 06/23/2014 11:24 AM »
All it would take to send a gaiaspore to another star, would be for the 24th centurys Elon Musk or Jeff Bezos to buy a habitat, fit it with ion motors and nuclear reactors to run them and to replace sunlight with artificial light, buy a bunch of uranium, thorium or plutonium, and send a million volunteers on their way.

Probably wouldnt even require any special individual or event. It can happen gradually, first the asteroids, then the Kuiper belt, then the Oort cloud, and then rogue planets that will eventually wander past other stars anyway. These worlds have huge amounts of hydrogen. Even if conventional fusion power never eventuates we could probably just detonate fusion bombs down hundred kilometer deep shafts in the ice every few months. Think of the quaint customs future pilgrims may practice to celebrate hydrogen bomb day a thousand years from now.. :)

Offline Tass

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Re: Reflections on the colonization of other planetary systems
« Reply #12 on: 06/23/2014 04:29 PM »
Fusion bombs tend to require fission bombs to set off. As long as you are using fission anyway,  I think straight fission reactors would be better, when counting the inefficiency and impracticality of huge subterranean explosions. But otherwise it might still very well go the way you describe. No reason to think you couldn't find thorium (or uranium) in the Oort cloud, and where nuclear reactions are concerned a little goes a long way.

No reason to think that fusion reactors won't be made either, really, but the point is even if we are being super conservative with the supposed new technology, this seems to be possible.

I agree that it will likely happen way earlier and on a smaller scale than what I described. People don't tend to wait with attempting something until it is easy. My point is just that if colonization of the solar system happens, then eventually it will be easy, so it will happen at some point before that.

Offline Stormbringer

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Re: Reflections on the colonization of other planetary systems
« Reply #13 on: 06/23/2014 04:40 PM »
nope nope nope! new schemes don't require bombs. they require lasers and a deuterium pellet.  no propulsion systems that requires ultra-miniaturized fusion bombs by the thousands will ever be cleared by any government.
When antigravity is outlawed only outlaws will have antigravity.

Offline Vultur

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Re: Reflections on the colonization of other planetary systems
« Reply #14 on: 06/24/2014 01:34 AM »
According to Grun et al. (2005), dust particles have a mass ranging from 10^-9 to 10^-14 g, or 10^-12 to 10^-17 kg, and a charge ranging from 10^-15 C to 10^-17 C. If we want the radius of the dust particle’s path to be say 1000 m while we are flying by at 0.10 c, then the strength of the magnetic field we will need will be:

B = mv/qr = (10^-12 kg)(3 x 10^7 m/s)/(10^-15 C)(1000 m) = 3 x 10^7 T

To generate a 3 x 10^7 T field, we would need a loop of wire carrying a current of:

I = B2(pi)r/u = (3 x 10^7 T)(2)(3.14)(1000 m)/(10^-7 Tm/A) = 2 x 10^18 A which is basically impossible, even with superconducting wires.

So I guess it would take way too much energy to have a magnetic field strong enough to deflect the dust particles.

It would be different if we were going much slower.

Reference

Eberhard Grün, Ralf Srama, Harald Krüger, Sascha Kempf, Valeri Dikarev, Stefan Helfert, Georg Moragas-Klostermeyer (2005) 2002 Kuiper prize lecture: Dust astronomy. Icarus 174:1-14

OK, cool, thanks for doing the math. So really really big ships with super thick asteroid material shielding are probably the way to go.

Offline Vultur

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Re: Reflections on the colonization of other planetary systems
« Reply #15 on: 06/24/2014 01:44 AM »
Hmm, I thought I'd already hit 'post' but it seems to have been lost in transmission...

nope nope nope! new schemes don't require bombs. they require lasers and a deuterium pellet.  no propulsion systems that requires ultra-miniaturized fusion bombs by the thousands will ever be cleared by any government.

Yeah, bombs aren't necessarily involved. But I'm assuming an off-earth, asteroid/O'Neill colony civilization. No environmental considerations, and such a civilization would have access to really destructive kinetic weapons (eg redirected asteroids) so nukes probably wouldn't seem especially frightening.


People seem fond of Orion style propulsion, but I see no reason not to simply use nuclear-electric. If you are going to take thousands of years for the journey, then you don't need high thrust. 

To accelerate a multi-billion-ton worldship to 1% of light speed in even 100 years requires quite significant thrust (billions of newtons).

And it wouldn't necessarily take thousands of years. Supposedly nuclear pulse propulsion can reach several percent of lightspeed. At 2% lightspeed you can do Alpha Centauri (4.3 ly) in about 215 years and Barnard's Star (6 ly) in about 300 years. And habitable planets or planetary systems aren't necessary for an asteroid/O'Neill colony civilization, just asteroid belts and comet clouds.

Quote
All it would take to send a gaiaspore to another star, would be for the 24th centurys Elon Musk or Jeff Bezos to buy a habitat, fit it with ion motors and nuclear reactors to run them and to replace sunlight with artificial light, buy a bunch of uranium, thorium or plutonium, and send a million volunteers on their way.

Essentially, yes, but I'd think the worldship-habitat would be custom built to survive super-high-speed impacts and the significant acceleration of the nuclear pulse engine, while O'Neill colonies/habitats might be pretty lightly built.

TRL's for technology
Fission 8 Well Nerva got to ground test.

Sure, but IIRC NERVA style fission rockets have Isps under 1000 -- not nearly good enough for interstellar. Even hypothetical gas core NTRs aren't good enough. Zubrin's nuclear-salt-water-rockets, maybe...  but they're not nearly NERVA-like. I think nuclear pulse propulsion is better understood than those (Project Orion, plus interstellar studies like Daedalus)

Quote
Fusion  2-3?

Fusion 1? (Well the Sun works)

For pulse propulsion, I'd say better than 1 -- nuclear bombs are a well demonstrated technology, and Orion figured out how to use them for propulsion, though admittedly it was tested only with chemical explosives (Hot Rod). Sustained fusion isn't required.

Of course, a basic Orion wouldn't give you several percent of lightspeed. Still, it's a start.

Quote
Ability to detect an Earth sized planet with sufficient detail to know it won't kill them outright. 3?

This is more likely to be colonizing asteroid belts, given that O'Neill colony cultures would convert well to worldships.  Anyway, this would be well after colonizing say Mars, so the boundaries for colonizable would be very wide.

Offline Tass

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Re: Reflections on the colonization of other planetary systems
« Reply #16 on: 06/24/2014 06:30 AM »
To accelerate a multi-billion-ton worldship to 1% of light speed in even 100 years requires quite significant thrust (billions of newtons).

True, in absolute terms, and compared to present day standards, it is a lot of thrust. What I meant is that it doesn't require huge thrust-to-weight.

100micro-g is enough to get to 0.01c in a hundred years. The ship is huge, obviously the ion engines would be too, (or they would be many).

Essentially, yes, but I'd think the worldship-habitat would be custom built to survive super-high-speed impacts and the significant acceleration of the nuclear pulse engine, while O'Neill colonies/habitats might be pretty lightly built.
 

Mostly agreed. You would likely custom build much of it. Light paths would need to be changed to use artificial light rather than sun, you could do away with most of the windows for better use of mass and area. Of course it is possible that starting from "of-the-shelf" habitats would be much cheaper than one that is entirely custom built.

As I don't see the case for nuclear pulse over NEP yet, I do not agree that it needs to be build for high acceleration. Impacts, yes, but they will all come from one direction* this will favor a worldship that is long and thin with just the front end reinforced.

*Not the band. Hopefully.     

Offline KelvinZero

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Re: Reflections on the colonization of other planetary systems
« Reply #17 on: 06/24/2014 08:45 AM »
OK, cool, thanks for doing the math. So really really big ships with super thick asteroid material shielding are probably the way to go.

Can't deflect an uncharged dust grain anyway.. Instead of a thick asteroid material maybe you can project something tenuous in front of the  ship that causes any incoming grain to detonate into plasma before hitting anything solid, and then that plasma could be added to the available reaction mass.

Offline gospacex

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Re: Reflections on the colonization of other planetary systems
« Reply #18 on: 06/24/2014 11:43 AM »
Exactly. A magnified version of Whipple shield should work wonderfully.

At these velocities, destructiveness of impacts is mostly from their energy, not momentum. (Because p=mv but E=0.5*mv^2).

A dust grain impacting a millimeter thick steel plate at 0.1 c explodes like a micro nuke.
It would vaporize a round hole in the plate, but if there is nothing behind the plate for hundreds of meters, the plasma would harmlessly dissipate into the vacuum, most of its energy now spent as photons (X-rays).
« Last Edit: 06/24/2014 11:45 AM by gospacex »

Offline mikelepage

I think we can assume people will attempt to make the journey long before we've expanded organically beyond the inner solar system (where solar energy is feasible).

Given that the entire homo sapien population has been estimated to have been as little as 1800 as recently as 70,000 years ago (sorry I don't have a source - I read this in an aricle about the Toba supervolcano eruption), I think we can assume a starter population sub 2000 without too much issue.

I can imagine you might have a situation by some point in the 2100 or early 2200s, where you have a few billion people in the inner solar system.  A comet/planetoid of 10-100km diameter is discovered to be passing near the inner solar system, and is on an escape trajectory which happens to take it past star X with known goldilocks zone extrasolar planets in say 5000-20000 years (at 70km/s this 4-16 light years).  Accelerating people and equipment up to 70 km/s is a lot easier than doing so for a large world ship type arrangement.

Those 2000 people would have to have some kind of fusion generator for creating warmth, and perhaps some propulsion, (it's a bit more realistic to talk about speeding a rock up and down by a few 10s of km/s than by significant amounts of C).  As the ride continues, they could continue harvesting raw materials for the creation of orbiting toroid space stations that would house their gradually growing population.  Perhaps by the time they arrive, the comet/planetoid itself is only a shell of what it once was, but the fleet of spacecraft that have been created from it - and maybe millions of people - are individually much easier to slow down into orbit around the target star than the massive rock would have been.

All of the people who arrive at the new planet(s) would have never experienced natural gravity before, yet hopefully their fokelore/communications with Sol would prepare them for the experience.  Many of them would probably choose to remain in orbit, but likely their tech would be at a stage where transiting to and from the ground would not be too much of an issue.

Unless some new and exotic form of space/time manipulation is discovered, this seems a far more reasonable type of speculation to me.