In space, today, we're in pre-aviation days: we're still using hot air balloons for transportation. We make them lighter than air (i.e. shoot them up in space) and let the wind (i.e gravity) to carry them places.
Imagine the most educated human 120 years ago is being told about planes heavier than air, air transportation over oceans, jet-powered planes, autopilots and fly-by-wire, not to mention people on the moon. He would say it's impossible, due to energy constraints. Today a daily JFK-NRT flight uses more energy than all the horses which lived two centuries ago would be able to produce in their lifetimes, combined (my math may be off by one order of magnitude: it's late here). Today we're this person. Educated enough to have valid arguments against it, but utterly incorrect.
The argment was valid argument till when" The Curies? Einstein?
100 years is a long time to figure stuff out. Thinking in millenia is impossible for us. "What would William the Norman have thought of all this?" is a pretty ridiculous thought and that's not even a whole thousand years ago. Nine year old crack babies today are more literate than most of his learned advisors and better technology meant sharper swords, less leaky boats and smoked bread. Their objections to the idea would have involved Loki chasing you around in a canoe.
Lets not get too cocky.
Well, make up your mind. :)
Edit: What on earth would cause you to downvote this?
Edit2: Thanks. I would still appreciate a comment if I'm 'doing it wrong.'
The author implies that we only have a rational interest in what happens during our lifespan. But many of us, through childbearing or other means, try to leave something of value behind us.
Irrational? Perhaps. But there's no reason pure hedonism should be any less irrational.
That said, we're not slaves to evolution and can make our own choices for our own reasons.
But when it comes to the vexed question of getting those genes to survive beyond our own mortal shell, the correct genetic strategy seems to be to protect our offspring, even at the expense of ourselves, so we commonly see parents sacrificing themselves for children, in many different species.
And that is of course the flow in Stross's argument about there not being any reason not to colonise. Sure, you can't be on multiple planets, but your offspring certainly can be, so if one of those planets goes up in smoke, your genes will continue on through your children on other planets...
What affects you is having children before you retire, because then you'll be fed and survive a lot more than otherwise. Evolution is a conclusion of that, not the other way around.
How much does/will the problem cost us?
IS there a solution?
How much will the solution cost?
Then you do cost benefit analysis and decide the best course of action. THEN you try to talk everybody else into it.
I'm happy to concede global warming is happening and will only get worse. Hell, I was one of the first people I know to understand and accept that. I just haven't seen the follow up yet. It's always "Yep, got yourself a problem there", but no solution offered other than "buy a Prius".
> Then you do cost benefit analysis and decide the best course of action. THEN you try to talk everybody else into it.
This is overly simplistic. Who is the decision maker? Democracies function as distributed consensus makers--very little _can_ or _should_ be dictated by some benevolent cabal. Moreover, for the rather complex problem of adapting _human civilization itself_ it is hard, if not impossible, to perform a cost benefit analysis. Where do you even get the possible solutions from if:
* no one but a few know about the problem and
* domain experts you consult with might have implicit
biases against the problem without significant
* the hypothetical cabal is composes of like minded
(hence like-blinded) individuals?
It's entirely possible we've gone past the point of short-term return. Still, the follow up, as you put it, has been to reduce or eliminate the primary sources of the problem:
* decrease the reliance of Heavy and Light industries on coal/oil
* decrease and reverse global deforestation
* decrease and reverse water vapor production from urban areas
> but no solution offered other than "buy a Prius".
I think that's willfully cynical of you, or uninformed. Even ignoring the obvious vested interest car manufactures have in misinforming us that a _different_ kind of car is a viable solution, the perverse effects a Car Culture has on an Urban environment--heavily paved, strongly lateral development--is likely unsustainable in the long-term.
Extremely simple illustration: Do you think people in Florida will be living 10 feet under water in 100 years? No, they will move before then. But they don't have to move now, so why force them?
Similarly, do you think we'll all be driving gas-guzzling SUVs in 100 years? Hell no. Oil just won't last that long, and our car culture will have died or switched to electric (or nuclear, or secret ooze) long before then anyway.
So why force the issue? I guess I'm just not seeing the urgency here. And whatever urgency there is, doesn't seem to be fixable in the short term. Ocean levels will rise. They already have. So let's focus on mitigation rather than the already failed task of prevention.
The fact that you think humans have by any means made the technological "leap" from coal to petroleum (or anywhere really) makes you look wildly ignorant on this issue.
I believe you might profitably examine your implicit assumptions about what constitutes "natural" and "gradual" adaptation of industry. As has been pointed out by another commenter, the progression has not been as linear as you have proposed: many industries in the world _still_ use wood as fuel, hence my prior deforestation comment. (Note that farmed wood promotes a monoculture ecosystem, effectively declaring creatures dependent on the prior heterogeneous environment unimportant.) Western countries have tended, historically speaking, to incentivise new industrial developments. Often this was done at the precipice of a disaster and done at great cost: much less money and life might have been spent had the work been gradual.
> Extremely simple illustration: Do you think people in Florida will be living 10 feet under water in 100 years? No, they will move before then. But they don't have to move now, so why force them?
Consider the crushing burden of mass migration, the vast human cost. There have been several such in this century already; you may go to visit them and learn why _gradual_ migration is vastly preferable. Further, do not misunderstand me: I am not advocating that all residents of Florida move at one time; this change should happen gradually as a part of a prepared plan. Such plans are difficult to construct when individuals such as yourself are content to kick the can down the road and let the future sort it out. Human civilizations adapt necessarily to their surroundings; done consciously such adaptations need not be the source of untellable human suffering.
> Similarly, do you think we'll all be driving gas-guzzling SUVs in 100 years? Hell no. Oil just won't last that long, and our car culture will have died or switched to electric (or nuclear, or secret ooze) long before then anyway.
Consider the economic implications of "running dry". So much of the United State's infrastructure carries the implicit assumption of cheap gasoline and diesel that to suddenly (meaning the sudden increased cost over the span of a decade, say) go without would cause significant harm to our economy and world standing, relative to those nations that are preparing. Again, I stress _gradual_ change, but such change must be sustained by a willingness to tackle the problem directly and _not_ simply be willing to let the future work things out. Surely they will, but at greater expense than we who now decide the course of the world can manage.
> So why force the issue?
I hope I have made myself clear. If not: the necessary adaptations of human civilization in many areas will be extensive, expensive and time consuming. We can mitigate the second concern by performing those adaptations _before_ they are vital. Consider that the upgrade of infrastructure as a part of regular maintenance cycles is more tenable than sudden overhaul. We need only come to an agreement on the way in which we will upgrade; this is impossible when influential individuals deny the basic premise or assert that the future will somehow more efficiently solve our problems though they be exacerbated by the passage of time.
> I guess I'm just not seeing the urgency here.
I believe the urgency is largely manufactured by a news media predicated on the spread of unease, over zealous Chicken Littles and anti-reactionary misinformation. We have a problem _now_. Our technological sophistication is such that we can prepare ourselves for this problem without the death or displacement of billions. What little urgency does actually exist at this point does so because the changes that must be made cannot be made fifteen years out; a period of fifty to seventy-five years, depending on global economy, is more reasonable. Cuts in significantly to your hypothetical one-hundred years, no?
> And whatever urgency there is, doesn't seem to be fixable in the short term.
No, it is not. This is why it is preferable to begin the process of adaptation before it is a matter of dire consequence.
> Ocean levels will rise. They already have. So let's focus on mitigation rather than the already failed task of prevention.
I believe you read my original statement with a biased eye. We must necessarily adapt--by the time we began to notice the effect our habits had on the global climate it was likely too late to reverse the process. That said, we would do well to live up to our self-given taxonomic title and not exacerbate the problem. It looks like we will continue, especially as developing countries fire up their own furnaces.
If we could stand building for the future and experiencing by proxy, a few more options become available:
e.g. We could transport a set of human "blanks" or a "blank" creating machine to a distant star at 10% of c. It would take a few hundred years. When it arrives and deploys, we upload our consciousness at the speed of light with no acceleration and deceleration into a "blank" human.
Copies of ourselves could be regularly transported to and from a distant star over a few decades.
A few technological breakthroughs would be required to make this a reality:
* True Artificial Intelligence. A machine that is capable of self-awareness and analysis.
* A complete understanding of the human brain and how to replicate the organism and it's contents.
* A complete understanding of the human body, the life support mechanism for the brain - and how to duplicate it.
* How to turn nuclear fission or fusion into propulsion at a high level of efficiency.
* How to build factories that can stay dormant for a thousand years, wake up and operate as well as the day they were built. This probably will be solved as a result of AI and the ability to create self-repairing and self-improving machines.
Many of these problems are in the CS and Biotech fields. That's what we do. Now get to work!
The long and the short of what I'm trying to get across is quite simply that, in the absence of technology indistinguishable from magic — magic tech that, furthermore, does things that from today's perspective appear to play fast and loose with the laws of physics — interstellar travel for human beings is near-as-dammit a non-starter. And while I won't rule out the possibility of such seemingly-magical technology appearing at some time in the future, the conclusion I draw as a science fiction writer is that if interstellar colonization ever happens, it will not follow the pattern of historical colonization drives that are followed by mass emigration and trade between the colonies and the old home soil.
Many people here are arguing for "magic tech that ... does things that from today's perspective appear to play fast and loose with the laws of physics." I suspect that many of the people doing this either don't realize they are, and/or don't really understand physical laws as we currently understand them.
I'm not holding my breath as neither me nor my children or grandchildren are leaving this planet, but look at the progress in technology we've made since the industrial revolution happened.
Magic wands? 1-computing, 2-wireless data transmission, 3-display (television), 4-rechargeable batteries, 5-touch interface, 6-price drops.
It was said about crossing the seas. It was said about colonizing the surface of the planet. It was said about diving deep into the seas and it was said about taking off ground. It was said about leaving the atmosphere. It was said about reaching out into space. It is currently being said by some about colonizing our solar system, and most people currently feel that the thought of us not colonizing our solar system is ridiculous, and in time the thought of us not leaving this solar system to go on to the next one will be considered just as ridiculous. "Scientists" like these often suffer from the common problem of never being able to see farther than their own nose; they constantly forget that we grow, and grow, and grow. Without meaning to sound pretentious and cheesy, here's a nice quote from a certain sci-fi series that came to mind: "It's our destiny to walk among the stars", and you can be damned sure that we will, providing we won't kill ourselves on the way.
There are other proposals, which haven't gotten much funding.
The whole field of propulsion research has been underfunded since the 1970s, probably because NASA didn't want to risk creating competition for their big job program -- the Shuttle...
Edit: The cool thing about this is that, assuming these technologies come to fruition, the entire project could likely be financed privately by a group of wealthy backers. You wouldn't need the massive bureaucracy of NASA or their dependency on Congress. You'd simply develop, test, then manufacture the (likely quite small) probes, then send them up and out on commercial rockets.
Re. the preservation thing, the question is exactly what counts as humanity. If you have limited resources and can only pick one, would you choose a planet colonized by biological humans who have lost all of the present civilization and language, and are reduced to stone-age conditions (assuming for the moment that the alien environment wouldn't kill them instantly), or synthetic beings with the sufficiently advanced AI with all human cultural knowledge and skills they'd need to survive on an alien planet and a cognitive and psychological makeup very close to actual humans they'd need to be able to raise babies into sane adults, and the ability to build more of themselves?
Basically, is humanity more about a culture or about being made of the correct chemicals?
Or not, as the case may be. That's why you send out many such probes. You would have to assume that most attempts would fail. You are, after all, attempting to transplant human life with no human oversight.
Either way, it's merely prolonging the inevitable. The Sun has about 5 billion years of fuel left, which is coincidentally about the time the Milky Way will collide with Andromeda, ruining everyone's day. The Sun would be far too hot to support life on Earth long before that, but let's assume we've moved to a more gentrified suburb. Even were humanity to somehow escape the Milky Way in the next 5 billion years, we'll still just be building sandcastle walls in an attempt to hold back the tide. I'm reminded here of Asimov's The Last Question, an excellent short story:
Desing whan ship that can do that for 20 people and then just keep sending them.
Though i doubt that is ever going to pass, so the only alternative for this "backup" plan is gov't funded expeditions.
Believing that what we currently know is applicable to humans in the future, that our current limits are immutable.
We know all the laws of physics, right? We know if the universe is finite or infinite(because we had traveled there and seen the limits), we know what creates gravity and exactly how electromagnetic attraction really works... the same way the people Socrates asked 2500 years ago knew it all, and Socrates himself did not knew anything(in his own words).
The same way people already knew everything about the small things before microscope invention(in their own words it was unnecessary because "why we want to see what we already know smaller?").
That someone develops better ways to control active fission(atom by atom) and fusion reactions, that someone discovers something new about the universe,that someone discovers how to create antigravity because understands what gravity really is, that someone discover the way to crack the code on aging on our DNA, that someone discovers why the light limit on vacuum is what it is and some way of going faster, all of this impossible, because we know it all.
What I find curious is that it's the people who don't know what we know who think we'll overturn what we know. Perhaps that's because it's easier to say "Oh, someone will overturn that" when you don't actually know what "that" is.
What we do have are human graspable descriptions of plausible moves based on our observations of chess pieces. We have no coherent theory on the game or why it is played. But that does not matter. A more important issue intertwined with this bias is: are notions of information and entropy more fundamental to how we formulate laws than anything intrinsic to energy and space?
We are wrong now, as well.
But to say that we are as wrong as Socrates is ridiculous. We are much, much, much closer to the truth now than we have ever been.
That's not the same as saying that space colonization is going to happen or that it's remotely within reach anytime soon.
If either Bussard's polywell fusion or focus fusion turn out to work, that'll be achievable within a couple decades. As Moore's Law continues and we get better at simulating plasma, it's not that unlikely that some form of fusion will work out.
There are a lot of possibilities for non-rocket launch, including various space-elevator-like schemes, laser launch, and mass drivers. Even without fusion, thorium fission could provide plenty of power.
It'd be pretty expensive and slow to travel to another star with fusion...but eventually, with large solar panels in close orbit around the sun, we'll have an awful lot of energy to play with, and just maybe we'll figure out efficient laser or microwave power transmission sometime in the next thousand years.
On the other hand, maybe we'll just colonize the Oort Cloud and gradually migrate to other stars over the next million years or so without really trying.
(And, not that I'm holding my breath for this one, but if Woodward's right about the Mach effect we'll get to other stars pretty quickly.)
As for the reasons...the resources of the solar system are millions of times what's available on Earth. Once launch is cheap it'll be a no-brainer to start mining the asteroids.
"As Bruce Sterling has put it: "I'll believe in people settling Mars at about the same time I see people settling the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live."
As for space colonization, there's enough of a romantic interest in it that I wouldn't think that the fact that it doesn't make economic sense would necessarily be a deal killer. There's also the possibility that some group would want to escape Earth at any expense. It didn't make a lot of economic sense for the Puritans to go to America, but they wanted out of the mother country.
It is? Maybe it's in the nature of some individuals, but three boats ain't no rocketship.
It seems unlikely at best that we'll ever attempt interstellar travel in our current organic bodies. The idea of taking along an atmosphere, food, water, and enough space to move around just seems ridiculous when you could stuff a human consciousness into a volume that, at worst, is the size of a melon, and at best considerably smaller. You'd also be able to add error correcting and redundancy to make the ship robust from radiation damage.
I suspect that any future spaceship will consist of perhaps 100 tons of computer and memory, designed with considerable redundancy and error correction. Perhaps 200,000 tons of shielding/fuel will be required, sufficient to protect the core computers and memory from interstellar particles, but also from the radiation from the ship's drive. Finally, you'd have a 1 million ton black hole sitting at the tail end of the ship, sufficiently large not to explode, but sufficiently small to have hardly any gravity. This would be fed by taking matter from the shielding to keep the black hole stable.
For further redundancy the ships might travel in small fleets, each acting as a backup store for each of the others. If one ship gets taken out by a stray piece of matter, at least you'd have a few more containing the same colonists.
The smart/educated few are not enough to offset the masses and for the masses it's simply not 'comfortable' to work on space travel; why would you, you already have a pool? Maybe poorer countries where people are not comfortable could be of use? Nah; you see around the world; when GDP gets over a certain level, out come the gadgets, mobile phones, ringtones, bentleys and other useless crap.
A very small (fractional) % of humans is busy with the problem of energy and space travel. If it would be a few actual %s of humanity we might stand a chance, unfortunately, the rest of the collective brainpower is spent arguing if the latest X Factor was won fairly.
I don't think we'll ever meet aliens either; after a certain time in the evolution, every race of 'intelligent' beings will invent paid ringtones, after that all chances of interstellar travel are gone.
Additionally you could explore the possibilities of fleets of nano sized probes, which over the course of thousands of years, confirm the habitality of an exoplanet, and build a crude nursery for sperm (which could be sent at a later date). This method makes the energy/momentum problems slightly less impossible.
The first is some breakthrough in physics that makes interstellar travel feasible. Not likely, but a staple of sci-fi.
The second is a series of improvements in nanotechnology making interplanetary colonies feasible (though less necessary).
And the looming confounding factor is that a "singularity" event might make all of this moot.
One interesting thing about sending some future human AI into space is that it could in theory 'power down' higher functions for hundreds or thousands of years as it travels to its destination. Upon reawakening, it would be in a new star system, with the cumulation of human knowledge in memory and enough tech to reproduce and start anew.
This is a problem because with 6.5 billion people we're using up resources. Fast.
Anyway, I see two potential solutions to this problem: one not-so-far-fetched and one incredibly far-fetched.
The not-so-far-fetched version is... hitch-hiking. Our understanding of the Universe is that it is full of mass wandering between stars. IIRC recently a planet-sized body was detected traveling between the stars.
Simple probability dictates that it is only a matter of time before a sufficiently large body travels through the Solar System with sufficient velocity (including direction) to reach somewhere else in sufficient time (but not too fast that we can't perform an orbital intercept) that we can essentially build a colony on it.
The far-fetched version is to use back holes as power sources  as this is, as far as I've read anyway, the only remotely viable method of providing propulsion without reaction mass to speak of and reaction mass is the death of any form of interstellar propulsion.
The answer to the Fermi Paradox  may simply be that it's too hard to leave our comfortable gravity wells and most (all?) civilizations simply run out of stuff before they get there.
I've also given the thought to "footprints". If you think about, say, a primitive tribesman. What do they need to survive in a sustainable fashion? They need a sufficient sized population (measured in the hundreds or low thousands) to avoid inbreeding and sufficient land area to provide a food source. This is probably measured in the tens or hundreds of square miles.
Imagine all they need as the footprint of a sustainable colony as that then dictates the minimum size of any spaceship.
Now imagine a more advanced society. 1000 modern humans would need an ENORMOUS footprint. Just think about computer chips. On any long voyage they'd break down so you need to be able to make new ones. That means a sufficient lab, technology, materials (or, in reality, the means to get more materials), all that knowledge and so on. Plus the size of the population goes up given required specializations.
This of course assumes that people would do all of these things instead of, say, an AI of some kind (which would actually solve a lot of problems).
That footprint is currently way too large to build any kind of interstellar vessel (IMHO). One of the trends I see in coming centuries is that footprint will reach a point of reducing in size. By 2100 I expect we'll be able to keep the sum of all human knowledge (or a close enough approximation) on an essentially mobile device. Advanced manufacturing techniques and materials may solve many of the footprint problems and so on.
As the footprint goes down, the viability of any isolated colony being able to survive increases.
The hitchhiking idea would also be ideal for the survival of humanity overall. With sufficient isolation, there will be cultural and genetic drift. If we're able to influence each other, that's a recipe for conflict. But a large mass passing through the Solar System is very likely a one-way ticket. There's no way to follow and no way to return (barring astronomically small odds of a repeat or inverse body).
Not really. You could also say that "simple probability dictates that it is only a matter of time before all of the air in the room is, at one point, in just one half." And, of course, you'd be wrong. When the odds are so staggering against something, it's more likely it will never happen than it will happen. We don't know how frequent such bodies are. But my guess is so infrequent that most solar systems in the universe will never have one travel through them.
Refresher on pressure: http://littleshop.physics.colostate.edu/activities/atmos1/Wh...
The gas molecules in the air don't know anything about the room's overall pressure, and don't individually obey any "pneumatic" laws. Pressure, in essence, is just a huge amount of molecules bouncing off a surface.
The air in a room is usually very evenly distributed, because it would be extremely unlikely that all the molecules happened to be in the same half.
Here's a link that might explain it better: http://webs.morningside.edu/slaven/physics/entropy/entropy3....
By way of extremely loose analogy, consider a large pea (1 cm in diameter) hanging by a string in the middle of a football stadium. Let's say that represents our solar system (minus the Oort cloud) and its environs. That's a slightly scaled-down version of Stross' analogy, where the diameter of the solar system (again, minus the Oort cloud) is about an Imperial foot. Now, without aiming, start firing individual molecules around the space. Those molecules are roughly to scale with a rogue planet.
On average, how long do you think you'd have to keep shooting molecules around before one of them passed within an inch of the pea? Within a centimeter? What about actually hitting it?
Even that's stretching the actual probabilities to the point of breaking, because your molecules are already in the neighborhood. For a more realistic example, take our 1cm pea and put it somewhere in some hypothetical space the size of the Milky Way, itself 6.4 * 10^9 AU in average diameter. At our scale of 1cm = 30 AU, the Milky Way would be a little over 200k KM across, or slightly more than half the distance between the earth and the moon. Now start shooting molecules around that space — from random locations, in random directions, again without aiming — and give me a call when one of them hits the pea...
A sobering thought regarding the inevitable "interstellar ramjet" suggestion.
Funny how solar sails seem like the easier option to build, but for interstellar travel you need enormous lasers near the home star to push the sail as it gets further away. Might as well build black holes with the lasers and solar collectors.
The black holes they would build are very very tiny, about the size of a proton. They are relatively light, about 600,000 tons. Such a body doesn't have noticeable gravity, it's too light to attract anything and too small to absorb it. The big danger from these are explosions at the end of their life. The explosions are serious if they happened near Earth, but safe at the distance of Earth to Sun. They're built near the host star anyway.
However, any amount of mass can (in classical theory) be compressed far enough to obtain a Schwarzschild radius, from which light cannot escape. This has only to do with the density, not the total mass: a very small mass can still cause a large curvature of space, though only in a very small region of space.
"""If one accumulates matter at nuclear density (the density of the nucleus of an atom, about 1018 kg/m3; neutron stars also reach this density), such an accumulation would fall within its own Schwarzschild radius at about 3 solar masses and thus would be a stellar black hole."""
I take that to mean that if I wanted to create a black hole of something with less mass than 3 suns, I would have to compress it beyond the density of an atom nucleus? Is this - even in theory - possible to do? Wouldn't you need some kind of "magic wand" (to stick with the articles authors choice of words?)
What happens if you take a large black hole, and you throw a lot of electrons into it? Does it get an electric field measurable from the outside? If not, how come an electron does have this field?
But in any case, the answer to your question is yes. Black holes have 3 quantities: mass, angular momentum, and charge. So, yeah, you can charge up a black hole by dropping charges into it and the charge would be visible to the outside.
Nuclear matter is very stiff. It can make a mass of the order of the Sun's, falling down with a significant fraction of the speed of light, bounce without becoming a black hole. So the pressure you'd need to make a black hole with higher-than-nuclear density would be, well, astronomical.
So, theoretically, you can get a bunch of very, very large lasers, focus them all upon a very small point, and if you pump enough energy into the system you wind up with a black hole.
using existing understanding of Nature - we can. At least the Universe provides the example of galaxies traveling with faster than the speed of light relative to each other. The same machinery is suggested in the
The opponents state that the energy requirement of the drive is higher than the whole Universe's energy. Obviously it is wrong statement as we already have whole galaxies mentioned above and whose faster than light speed obviously takes less than the whole Universe's energy.
By the time we acquire the means to leave the solar system society will have transformed so completely that it's impossible to predict what our goals will be. Resources and population are not likely to be problems at all though.
Chips are small and light enough that you can bring along a thousand times more chips than you need, at negligible additional cost. PCBs are a bit more trouble, but those are much easier to produce and recycle.
Actually 7, in 1 to 3 months.
Also since a large genetic pool comes with the colonists, it limits genetic drift.
Also if you were hitchhiking you would need a massively plentiful source of fuel in the target environment because it doesn't have the sun pumping energy into it.
He/she never claimed we will. The claim was that we the entire human knowledge will fit on a mobile device.
If you would have said a man would walk on the moon 100 years ago, you'd be regarded as crazy.
What happens in the far future is impossible for us to predict right now. 100 years ago we didn't know everything there is to know, and now we don't either. History is full of these kind of closed-minded extrapolations.
Appropriate other post on the frontpage right now: http://news.ycombinator.com/item?id=2639701
So you're saying there's a chance!
From the Tsar Bomba article on wikipedia: "Since 50 Mt is 2.1×1017 joules, the average power produced during the entire fission-fusion process, lasting around 39 nanoseconds, was about 5.4×1024 watts or 5.4 yottawatts (5.4 septillion watts). This is equivalent to approximately 1.4% of the power output of the Sun."
That's a lot of power right there. Now to harness that :)
Accelerating the space shuttle to 0.10c :
(2,030 t * (0.10c)(0.10*c))/210 PJ = 8700 (wolfram alpha)
2,030 mass of space shuttle in metric tons
210PJ the energy from tsar bomba.
But then you have to add in the weight of the bombs too.
since they are each 27,000kg and then you have to sum it up to get to something that can approach 0.10c (and I don't remmember how I had figured that one out)
And what says once you get to the other planet you can't fill the tank with nuclear materials over there for the return trip?
What? No it doesn't. We can do massively better than this, right now. As in, today's technology. No problem.
Why haven't we? It's frickin' expensive.
But the long-range probes we've launched have been pretty damn near coasting their entire trip, with a few course corrections. They were pushed, and now they float until they gain sentience and come back to say "hi". If they had a huge-ass rocket attached to them, such as would likely be on anything interested in going any distance at any kind of speed (ie, human-carrying ships), they'd get where they're going a lot faster.
Next up, to get to proxmia centauri in 42 years with some hand-waving to make things simpler and 100% efficient energy usage:
>To put this figure in perspective, the total conversion of one kilogram of mass into energy yields 9 x 1016 Joules. (Which one of my sources informs me, is about equivalent to 21.6 megatons in thermonuclear explosive yield). So we require the equivalent energy output to 400 megatons of nuclear armageddon ...
Where did 400 megatons come from, if it's equivalent to 21.6? And if 400 is "the same as the yield of the entire US Minuteman III ICBM force", I say that's a miniscule amount of energy, especially once it's divided by 20. Crank it up another 10-fold beyond 400, and we're still talking modern-day terrestrial-level achievable energy without breaking a sweat.
>So it would take our total planetary electricity production for a period of half a million seconds — roughly 5 days — to supply the necessary va-va-voom.
Not bad, really. We're pretty inefficient right now. Make it cost a few times that - we'll be producing that in a week before we can even get a lame v0.1 ship built and in trials.
All in all, an interesting read. But it feels more like a half-accurate rant. We're waving magic wands to get 100% efficiency and 2000kg, but we're not waving magic wands to get away from conventional rockets and today's energy production levels?
I'm entirely on their side that our tech today can't get us to the stars. Totally. I agree, the energy needed is quite literally astronomical, and we're not even close to it. But we keep finding weird things with our science - I'm not writing it off entirely. And I don't see why people seem to imply that we must leave from Earth - why not mine the asteroid belt to provide the fuel at our leisure, and build a truly massive ship? We're not going to aim for the stars on our first go, we'll be living in space for a long time before then.
And he is getting away from conventional rockets, the 2e18 estimate assumes that the energy required to move the ship is coming from elsewhere, not carried along with the ship.
So he assumes a very small ship and mysterious ways of propelling it in order to sketch an estimate of the minimum amounts of energy involved. Ripping an even bigger hole in physics might throw acceleration and momentum out the window, but assuming 100% efficient transmission of energy across 24 light years already requires something pretty strange to us.
(his comparisons to present day production levels seem more illustrative than pessimistic)
In one short century we published more books and amassed more knowledge than all centuries past. Together. And we built the tools to search it and process it into meaning.
Traveling to another star is a formidable problem and doing it Newton style is not impractical. But if the past century teaches us something, we are a species prone to invent magic wands.
Besides that, we all know how futile is to try to predict the future. We can only see and express it in our own terms. The future is as alien to us as Twitter would be to my grandmother (who would be turning a century if she were alive).
James Arthur Baldwin
That being said, I don't disagree with most of the post.
Some other things man will never do: http://www.rense.com/general81/dw.htm
There seem to be two common misconceptions about the colonization of space:
1. People will colonize other planets. The notion that future generations will desire to burrow into other planets is as strange as expecting people to build a new city by digging caves in a cliff wall. Just as we now build apartment blocks and ranch houses, we will someday build custom habitats that aren't continually ravaged by earthquakes, tornados and spring floods.
2. Reaching the next solar system will be momentous. People will populate neighbouring solar systems just as our ancestors moved from Africa to other parts of the world... gradually from one generation to the next, each one drifting a little further into the Oort. One day a habitat that has its own artificial star within will move from the most recent piece of raw material to the next, not realizing that the one orbits our distant sun while the other orbits another star entirely.
Barring catastrophe at home, this future is likely. It's just the same story that's been happening since Lucy's family left the Great Rift Valley.
His arguments are related to interstellar travel as an endeavour that is undertaken as a gravity well to gravity well transit. My argument is that planetary colonization and travel from Earth to the close orbit of Proxima Centauri or any other star is not the only method by which humankind will reach beyond this solar system. Does that not address his arguments?
Granted, space colonization would be much more expensive than any very long-term or symbolic project we do now, but it's not out of the question that future societies would be more inclined to do stuff like that than 21st century anglophones. If so, none of Stross's barriers are necessarily deal-breakers.
For example, I don't think Hitler would have spared any expense to seed another world with Aryans, regardless of whether it made any economic sense (since when do humans only do things that make sense?), and the 420 year time frame wouldn't seem like much to a man who thought he founded a 1000 year Reich.
"We won't make it to america unless we build ships as large as a stadium and can put a thousand slaves with oars in them. But then, where are we going to put all the food to feed them? Well, we let them die and throw them in the ocean, only the stronger will deserve to be called the first american settlers"
We don't know yet what the future may teach us.
Personally I am an optimist on these things - in 1711 you could not have imagined regular Aircraft - something we take for granted today much less Spacecrafts. Electricity, Computers, Cell-phones, Internet, etc would have been inconceivable.
Today we have been to the moon ~40 years ago. Villagers in India use cellphones and electricity and a fifth of humanity is interconnected via the net.
So I have to believe that by 2311 we will have cracked the problems around Interstellar travel and be living around a different Sun than our Sol.
Anything else is just underestimating the Human Spirit.
(Otherwise it's not just human colonization you're talking about -- it's Terrestrial biosphere colonization, which is a vastly more complex matter than most people seem to be willing to contemplate.)
So it is possible for a life form, human or extraterrestrial, to build such a civilization seed which contains enough energy reserve and machinery to sustain life activity restoration and live form rebirth. Throw such civilization seed vessel like a bullet toward a distant solar system so that the energy of the target can be used to trigger start of development and we have our space travel capacity.
This is not how we'd naturally imagine interstellar travel, but the important point is that this proves that it is possible without relying on exotic or hazardous hypothesis. We should also keep in mind that there is still the possibility to tap into the dark matter as source of energy. While this is still very uncertain, it should be known and well accepted By now that interstellar travel and space colonization is possible.
I would like to add to this that if human life is a result of a natural process, there is a very high likelyhood that we are not alone in the univers and that other entities are likely to have started colonization already a long time ago. As we can see from earth civilization history a key factor to perserve its liberty and life autodetermination is the mastering of science and technology, intelligence and defense capacity. While there is still a need to protect ourselves from oher humans, in which we spend and waste a lot of ressource, the clock is ticking, and other civilizations may be developping much faster and efficiently than humans. It is no hard to see what it all implies.
"Kiwi developer Glenn Martin, who has been working on his flying machine for 30 years, intends to make it available on the market in 2012 at a cost of about US$100,000. Last month, the jetpack made its first high-altitude test flight, taking a dummy pilot to 1,500 meters under remote control while Mr Martin watched from a helicopter."
For more, http://www.telegraph.co.uk/technology/8566096/Martin-Jetpack...
Humans will make it to the asteroids, to the rest of the Milky Way, and fill the Universe.
In a few decades from now, the energy necessary for such a long distance space flight could come from half a ton of anti-hydrogen.
Brief article summary: https://secure.wikimedia.org/wikipedia/en/wiki/Breakthrough_...
But one could sum up the essay as such:
"A man from the XXIst century said it it's impossible to leave the solar system"
Perhaps we should wait for what the man of the XXIInd century might have to say?
We'll need a couple of magic wands, but we've already built a lot of them.
Remember that in the early XXth century going into space was still science fiction.
Nor should the future bankruptcy of your country concern you as long as it happens after you're dead. Even if your descendents have to pay the piper for it.
Like it always has, something will come along that will change everything.
alternatively upload me and I'll put myself in a more suitable interstellar body.
Edit: Curious about downvotes?
Perhaps not in ways that solve these issues. But we're still almost certainly wrong about things we consider very fundamental.
As an example there will not be a theory which says "You can lift yourself up" and suddenly people grabbing their own belts could lift themselves up into the air.
Any future theory will predict exactly the same things as current theories on the cases where current theories have been experimentally verified.
Come on, wake up a bit. It's a reasoned essay, explaining his assumptions and exclusions, not just some babbling end-of-scientific-progress scaremongering.