Searching For McGuffinite
Humans will reach the planets in this century; at least there is a rather good chance that we will, without ever needing to be explicit about Step Two. The inherent coolness of space travel, along with national vanity and parochial economic interests, has turned out to be sufficient for half a century. There is no inherent reason why this should not remain the case into or through the midfuture, as our steadily growing capabilities carry us outward.
What this highly plausible space future does not have room for, however, is most of our favorite space tropes. Last post I made a comparison of space to Antarctica. The popular literature of polar exploration is tiny, and most of what there is deals with the early days. (Amundsen and Shackleton are the two names I remember off of hand.) Real space travel may turn out very similar. People will work very hard and spend a great deal of money to see to it that dramatic adventures do not happen in space.
Nor does the human scale of the thing lend itself to space opera. In the early interplanetary era - and, in all likelihood, for a long time after - there may be hundreds of people in space, but probably not thousands and certainly not millions. There will be a space economy, but no economy in space: the ships will be transports, not liners, and certainly not tramp freighters. (Sob!)
For story purposes this is not what we want. We want a lot of people in space. We want the outposts to grow into bases, then towns, then cities, and of course we mostly want them to end up fighting space battles with each other. For this we need a justification.
At least in 'Murrican science fiction, the profit motive is enshrined as probably necessary and certainly sufficient reason to go into space on whatever scale is desired. This attitude is not just confined to the libertarian-minded; Evil Megacorps in Space are a variation on the same theme. (I am not sure how it is elsewhere. Clarke's space midfuture, at least in his earlier stories, seemed not unlike the 'realistic' vision I portrayed above.)
The most popular profit motive has been mining. This is only natural. Mining fits the broad Western trope, and it does take people to the most Godforsaken places.
You have to make a few friendly assumptions to get space mining for terrestrial use to pan out (so to speak). But the subtler problem is then what? Suppose we learned that the rings of Saturn are full of McGuffinite. There is not going to be a rush of would-be Belters heading out to be Ringers instead.
Instead there will be some very big consortium formed, or a handful of them, probably with more than cozy relationships with existing national or para-national space agencies. A very focused program will develop the technology to do one thing: Go to the rings of Saturn, extract McGuffinite, and bring the stuff back to Earth. This effort will not go anywhere or do anything else. (With a limited but potentially important exception I'll get to below.) It will involve the necessary minimum number of humans in space, especially Saturn space; from every operational perspective the optimum is zero.
And once in place, beyond Earth orbit the mining operation may scarcely interact with other space activity. Mining transports headed for the Rings do not stop off at Mars or Titan. The experience of developing countries is that resource extraction infrastructure is not very helpful. The rail line runs from a seaport to the mine, and even the seaport is chosen for access to the mine, not its potential as a general trade entrepot.
Resource extraction is an economic monoculture, and like other monocultures it does not support a rich ecosystem.
The most popular political McGuffinite, a great power arms race, has a rather similar problem. As earlier discussions here have shown, great power warfare scenarios offer little role for space cruisers in whatever form. Only for laser stars that may well be robotic, and kinetic killer buses that will certainly be.
A somewhat different matter is resource extraction in space for use in space, such as the popular lunar shipbuilding industry. This is not McGuffinite, because it is not a reason to go into space. It is something you do only when you are already in space, and in a big way.
And of course there are other complications. Building spacecraft requires an enormous industrial base, and every pipe wrench has to come up from Earth unless you set up a pipe wrench factory or at least a fab. The lower energy cost of orbit lift from the Moon can evaporate quickly when you consider all the front end and operating costs.
It will be a long time before we have production industries in space.
An exception could be propellant, because space travel uses so much of it, and it is fairly simple stuff. Once we are regularly going somewhere with accessible volatiles, there will be consideration of obtaining propellant from them. This is not as simple as it is often made to sound. For example, all the ice on Mars is no use to deep space craft unless you lift it to Mars orbit, a major spacelift operation even if you can do it with a one stage vehicle. And there is no space infrastructure on Mars but what we take there.
I would say that the early interplanetary era ends on the day that a ship makes a routine burn in Earth orbital space using propellant that did not come from Earth.
Propellant production differs from McGuffinite mining in one crucial respect: It is inherently tied to the rest of the space infrastructure. And space travel is no longer entirely geocentric; for the first time, some of what happens in space stays in space.
Still a long ways from the Solar Confederation versus the Planetary Union, but everything has to start somewhere.
If I were working out a future history with a serious illusion of plausibility, I would stay away from McGuffinite. It is an ancient, overused crutch, and not a convincing one. Given worlds enough and time (and both are available), exports to Earth may well arise, as consequences rather than cause of space exploration. These may be - almost certainly will be - entirely unexpected and counterintuitive.
To quote myself, from last year's 'A Solar System For This Century':
Someone will find out that burgundy grapes grown in a Martian greenhouse have a distinct flavor. Pretty soon they are shipping back little airline size bottles that sell for $500, with just enough for a toast, and 'robustly Martian' ends up being used to describe burgundies from lands where Charles the Bold once ruled.Unlike McGuffinite, Martian burgundy doesn't have to be globally profitable - paying back the cost of going to Mars in the first place, or even the cost of the transport system. It only needs to be locally and marginally profitable ('marginal' in the formal economic sense, not precarious). Those little bottles only need to pay for themselves, their contents, and the extra propellant to get them to Earth. Ivan Q(ing) Taxpayer already paid for the transport ships, though you'd never know it from the collected works of the wine industry council.
Multiply such serendipities and, gradually, the human space ecosystem grows more complex. Oenologists now have a place on Mars, bringing a body of specialized knowledge and also an outlook on life and civilization.
This sort of thing takes time, probably lots of it, because it cannot be planned, it can only evolve. It may not happen. Indeed it probably will not happen, even in a future of interplanetary travel, because space travel is inherently so difficult.
But it is the one most likely path to get you from Earth to space opera.
The imagined image of Cassini, as so often, comes from Atomic Rockets.
274 comments:
1 – 200 of 274 Newer› Newest»Tobacco and sugar were not crucial to the economies of Europe- the the formed a small but very userful part of the european diet, the former was a luxury.
Nevertheless, they drew in massive profits for investers and allowed the North American colonies to survive- it was their prime export.
It might be amusing to imagine that the biggist imports from Earth to the off-world colonies would be people with PhD's, and that the major 'product' that they 'ship' back to Earth would be knowledge. I'm not sure how you would work this; maybe people would speculate in 'science futures' or 'information credits' would be exchanged for currency. I'm not sure what the exchange rate might be, but seeing "Titan Science Futures' listed on NASDQ or NYSE might happen, some day. It isn't as though we haven't had simular situations in our past...just look at the 'Tulip Bubble'!
Ferrell
Space itself might be the McGuffinite. The Japanese had to literally BUILD an island to house Kansai International Airport, and it is currently sinking. It ended up being cheaper to build more land than to deal with the local inhabitants. Perhaps there will be some process which produces a critical something that is so devastating to the environment that production is moved off world. Likewise, Earth being the sole biosphere of humanity might push any activities that endanger that off world.
Our host, Rick, states:
"If I were working out a future history with a serious illusion of plausibility, I would stay away from McGuffinite. It is an ancient, overused crutch, and not a convincing one."
And what do people do? They immediately engage in justifying McGuffinite. Classic.
What we need is, quite simply, people in space. Once we have a reason to put people in space then we can justify in-situ mining to supply their activities. Once we have a significant number of people in space then they will necessarily be doing stuff anyway, and so some of that stuff may end up earning them money on the interplanetary market. Once we have enough different groups of people in space, they can decide they don't like each other and build war fleets.
First, however, we need people in space.
Why would we put them there, besides "Because it's cool!"?
("Because it's cool" might someday be an acceptable excuse, but only if space colonization ever becomes sufficiently cheap that a group of dedicated hobbyists can afford it. This... does not seem likely in the near future.)
Citizen Joe:
"Perhaps there will be some process which produces a critical something that is so devastating to the environment that production is moved off world. Likewise, Earth being the sole biosphere of humanity might push any activities that endanger that off world."
It amuses me how easy people think it is to wreck the planet. Do you flee the country every time someone lights a campfire?
Don't think of it as wrecking the planet, more like overwhelming it. Take a look at the population projections for the next few decades (and the last century) We are very rapidly running out of room.
Sending even a few million people into space would do little to relieve the overpopulation pressure from seven billion people.
I would like to say that one reason to move up into space is manufacturing. Move a lot of the dirty and nasty process into orbit, and allow much of the earth to go green again.
But you would be faced with much the same problem going down the gravity well as going up. One would need to move a lot of tonnage, and for that you would need a rather large series of space elevators. Shuttles and re-entry pods just wouldn't work in this circumstance.
And what about the people on earth? You can't just remove the factories and leave them unemployed.
Ya, you don't send people up, you send up anything not related to or harmful to the environment/life support. If you can do something in space, rather than planetside, then you send it up.
While resource extraction may not lead to fleets of duelling space battleships (sob!) we combat junkies can still write our stories.
Historical far-off resource extraction booms weren't peaceful places: bushrangers and other colorful types hung around the California and Australian goldfields. Current-day sites like the Nigerian oil delta or the copper mine in Papua New Guinea have their share of bad guys with guns too. (Although I'm being Western-centric here, from the viewpoint of the Nigerians or Papua New Guineans, these are not far-off places.)
Writers of Westerns managed, so we should still be able to have arguments about the merits of different types of space weaponry even when the number of participants rarely gets into double figures.
I think the extraction of resources such as remass in space will create new opportunities. The process of extraction will release all kinds of other materials as byproducts, and people will probably find some use for that.
Consider:
on the lunar surface, a strip miner can process a square kilometer of regolith and the plant can extract an estimated 600 tons of volatiles:
H2 201 tons
H20 109 tons
He 102 tons
CO 63 tons
CO2 56 tons
CH4 53 tons
N2 16 tons
3He 33 kg
The Helium-3 is worth 7.9 million dollars/kg in 2000 dollars, more than the total value of the other volatile elements and metals combined!
In this instance the 3He is the McGuffinite, but most of the other elements have high value as chemical feedstocks or volatiles for life support. There are also metals, such as titanium, aluminum and iron, and even the slag has value as radiation shielding. A mining consortium can branch out first off by using the elements to close their own life support cycles, then selling materials to other companies/entities which are seeking to expand into space for whatever purpose.
The fact processed material is available will make it more attractive to consider doing something in space.
Realisticly, most human offworld outposts for the forseeable future would be scientific in nature...at least to begin with. The desire to 'make ones fortune' is strong. Some will believe that going offworld to sell some product or service, get rich, then retire back to Earth in style is the way to secure their future...there may even be a competition for slots on the transports out. McGuffinite isn't a physical thing, but an intangable...a desire to 'make it big'. Although most of those people would wind up going bust or only breaking even, possibly end up becoming permanant residents and the start of a real colony. Eventually, other people will set up businesses to support those accidental colonists, as well as the growing travel and trade that those people living offworld would generate. It may not be an object, but what I've described is as close to McGuffinite as what will likely occure, in my opinion.
Ferrell
Ferrell: "...and that the major 'product' that they 'ship' back to Earth would be knowledge."
Citizen Joe: "Perhaps there will be some process which produces a critical something that is so devastating to the environment that production is moved off world."
& maybe there are experiments that are so risky that you don't want to do them on earth. Suppose the fuss about the Large Hadron Collider maybe destroying the earth by making a black hole had some real justification. In that case, building it in high orbit would be the way to go, so in the worst case all that is lost is some expensive equipment & maybe a few dozen lives, rather than an entire habitable planet & everyone living on it.
Mr. Blue:
"I would like to say that one reason to move up into space is manufacturing. Move a lot of the dirty and nasty process into orbit, and allow much of the earth to go green again."
Keeping pollution safely contained in sealed dumps on Earth is surely easier than keeping breathable air safely contained in sealed habitats in space.
Also consider the environmental damage that could be done by all those rocket launches themselves.
Hugh:
"Writers of Westerns managed, so we should still be able to have arguments about the merits of different types of space weaponry even when the number of participants rarely gets into double figures."
The thing is, this is more likely to lead to handgun shootouts inside a dome city than to duelling combat ships.
Ferrell:
"Some will believe that going offworld to sell some product or service, get rich, then retire back to Earth in style is the way to secure their future..."
The problem is, for people to think that trying to go to a colony to earn money is a good idea, first the colonies must have ample money to spend.
Now you certainly have advantages in starting a business on a new colony - there will be less competition, which may make your services more valuable (and thus profitable) even if the total amount of money isn't actually that much. But still, there's a limit on how far you can take this. The colonies need to have a decent amount of resources before this can become practical.
Jim Baerg:
"Suppose the fuss about the Large Hadron Collider maybe destroying the earth by making a black hole had some real justification."
While we're at it, suppose the moon is made of cheese. That would surely make colonization easier.
Consider the possibility that the purpose of the first large settlements in space lacks a significant profit motive.
A consortium of wealthy individuals decides to leave their mark on humanity and does so by funding the establishment of off-world settlements, making humanity into a multi-planet species.
A potential future is the first Martian settlers never plan to come back to Earth. All the ships that leave Earth for Mars are one way and the ships themselves are de-assembled and de-orbited on arrival at Mars to provide for the immediate needs of the settlement.
This continues for a period of time and possibly with various pauses before the species is a single interplanetary [i]civilization[/i] again. The Martians, having effectively grown to survive on their own are now a market for Earth goods and may have something to trade back.
What if the Illustrious Leader of some hermit state 200 years future decides that it need needs to follow the path of Space-Juche and build space habs full of plump, happy space workers? In orbit they will be safe from capitalist infiltrators and will be able to function as a perfect neo-communist unit.
Of course all the international observers point out that there is no way that this space-mad hermit kingdom can sustain a long-term commitment in space. It makes absolutely no economic sense. They would be much better served investing in there domestic economy. The technology they are using is woefully out of date. They are stripping the countryside bare in order put a few thousand of their most elite into orbit for the deranged and unworkable goals of a power hungry dictator. And sure enough, after a few decades there are a half dozen habs will a few thousand workers in orbit, precariously hanging on to their existence, while the Illustrious Leader comes to an ignominious end in a coup in his homeland.
The international community is in a quandary. While they debate, one of the habs fails catastrophically. There is much wringing of hands. Finally someone decides, for humanitarian purposes of course, to send up experts and resources to maintain theses habs until some sort of evacuation can be arranged.
Experts come and go. Some habs are evacuated. Some get pressed into service as labs, hotels, whatever. Humans are in space. Humans in space are the McGuffinite. Once they are there living it,once some crazy has invested billions of dollars to put stuff up there, bureaucratic logic will always find an excuse to keep sending up money until someone stumble across a way to make it work.
I know that was really fanciful. But it is was fun to imagine.
(And before anyone says that the international community would never allow a mad dictator to put habs up in orbit, I am sure someone 50 years ago would have said the same thing about letting one have nukes.)
There's no way I'm catching up now :(
I just finished the comment thread on Industrial scale :/
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Milo:
I used an example of a fuss over a hazard that no reality to illustrate the point that there may be some experiments that really are outrageously hazardous.
How about experiments with self-reproducing nanotech as something that is both potentially very useful & extremely hazardous.
For that matter in another thread, the claim that atmospheric nuclear tests created an unethically large hazard for people all over the world.
My example was poor, butthe point stands.
Thinking about it, maybe the search for McGuffinite might propel people into space...kind of like the Holy Grail; no one knows what it is, but they will know it when they find it.
Ferrell
Jim Baerg:
"How about experiments with self-reproducing nanotech as something that is both potentially very useful & extremely hazardous."
We already have self-reproducing nanotech. They're called bacteria.
Okay, so I guess some of those actually are hazardous...
"For that matter in another thread, the claim that atmospheric nuclear tests created an unethically large hazard for people all over the world."
So you're going to perform your atmospheric nuclear tests in space instead? Oh wait... no atmosphere.
Ferrell:
"Thinking about it, maybe the search for McGuffinite might propel people into space... kind of like the Holy Grail; no one knows what it is, but they will know it when they find it."
So, the scientific research excuse again. We don't know what we'll find but we're sure there must be something interesting.
Funding for a research proposal that goes "we have no idea what we're doing, but something good might come of it, maybe", however, is not so easy to find.
If profit is not a likely motive, there is always Politics and Religion.
Because face it, those two things cause people to do some rather interesting (and dumb) things.
It may be that the motive for the first off earth colonist is to get someplace where they can practice their ideology with minimal interference. And it may be that the government of the ‘old country’ may encourage these nuts to go- you get cannon fodder for the difficult early work of colonization, warm bodies to claim ground for your flag, and you get to thin out the ranks of people you just don’t like. It’s a win-win situation, except for those early colonists who’ll go through a lot of hardship if they’re lucky.
And using undesirables as colonist has a very long history for that very reason.
But even if there is a frightful death toll among the colonist, there are those who would still want to go. People are kind of dumb that way. They would see it more as a challenge, especially the type of person who wants to emigrate in the first place.
Space-based solar power could be a motivator for getting people into Earth orbit, since the power satellites would probably need to be assembled in orbit, and this task might be too complicated or fiddly for robots to perform. Of course, advances in robotics and telepresence could make construction workers in orbit as obsolete as Clarke's manned communication stations.
R.C.
R.C.:
"Space-based solar power could be a motivator for getting people into Earth orbit..."
It's not even a motivator for putting solar power collectors in orbit. The cost is no way justified by the increase in efficiency.
It’s funny. I have always said that “parochial economic interests” are the reason we don’t already have a station on Mars.
It may be that the motive for the first off earth colonist is to get someplace where they can practice their ideology with minimal interference. - Mr. Blue
For some odd reason, I'm getting the image of a Jonestown in space from that statement.
Anyway, back to the blog topic in hand. From the comments I've read so far in this and previous blog entries, there's a general consensus that there needs to be a high enough population of humans in space to justify the creation of any space-based infrastructure or space-support economy. The only questions would be "how" and "why". McGuffinite reasons have been a staple, but so far they typically represent something grand that actually grants profit to entrepreneurs that instantly marks their placement in history rather then retrospective. I have yet to recall a mcguffin reason that was essentially mundane in appearances.
One thought, though not the most ideal, is that the maintenance and upgrade of artificial satellites would be financially cheaper then to send up a new satellite as technology advances. Especially since the launch of a small satellite component would be arguably easier and cheaper to send into space then an entire satellite. Again, this would not be the best reason, but for the sake of argument lets assume that it is. This thought also leads to the question of how would these satellites would be repaired: human astronauts in an orbital station or robonaut drones? Naturally, one would argue that drones would be easier to maintain since there's no life support attached to them but then t here's also the argument that (as machines) drones would still require maintenance and troubleshooting which are much easier on location then from a distance. Additionally, there's also the question of if the human astronauts should only be sent to maintain and repair such satellites and drones when the need arises or have a tour of duty onboard the orbital station when the time between the identification of the problem and the repair job is crucial. And even if the repair astronauts are under the tour of duty program, there's also the question of life support logistics between sending such finite expendable supplies over space-based agriculture upon said station.
For the sake of argument again, let us assume that the semi-self sufficient orbital station with repair astronauts (with or without robonaut drones) were the better alternative to satellite repair and maintenance. Then someone gets the idea that if satellites could be maintained and repaired in space, why not assemble such satellites in space? Then a new industry of satellite assembly, if not construction, is formed which can eventually evolve into orbital stations that specialize in the assembly/construction of different weather and communication satellites. Even orbital assembly/construction stations whose sole purpose is the service of military satellites of their sponsor nation or nations. Thus we have fulfilled the requirement of people in space that must be supported and, ultimately, defended.
Granted, the above idea is full of assumptions for it to work, however much of the excuses for a space-supported/based infrastructure are all basically assumptions and conjecture since we have little history on the subject. In short, we simply don't know what will provide the spark for rocketpunk and/or plausible midfuture that has been envisioned. We simply have to do a trial by error just to see what works and what doesn't and which are financially plausible. Though then again, that is the history of space flight and space exploration isn't it?
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Truth be told, it is highly unlikely that early humans in space would bring much of anything to earth, it's just to expensive. We have plenty of untapped ore on Earth, and with Earth based alternative energy we could easily power the entire world for generations.
It might be amusing to imagine that the biggist imports from Earth to the off-world colonies would be people with PhD's, and that the major 'product' that they 'ship' back to Earth would be knowledge.
Scientists are already in space exporting knowledge down here, the reason we don't go to the Moon anymore is because there is nothing there left to see, and Mars is a big maybe for return flight. So why go to space?
One reason for going to space is going to space itself.
Because we want to be there, the same reason we wanted to go to Europe and Asia from Africa, the same reason we wanted to go to America from Europe and China, there is land there, and our yearning is to fill it.
It's not as simple as that of course, but that's the gist of it.
Population is an issue too, and not over population, but under population, who is to say that 15 billion educated Humans is enough?
As a species our goal is to have as many of us as it is bearable by our environment, because we want new minds, and new gene mixes, and new ideas! Therefore expand the environment, hope for 15 trillion people by the 3rd millennium.
This I think is the greatest reason for going into space, it simply increases our chances for survival, and that's whats important in the long run. Spreading out trough the Solar system will make us pretty tough to be wiped out by an asteroid blast, or an airborne virus.
These of course are not profitable things, but important ones and thats why the first colonies will be government backed, and totally unprofitable. Their only purpose will be to prepare to accept more settlers to enlarge the gene pool, and all space economy will develop around these colonies. Yes i count space stations as colonies too.
There 3, or at least 2.5 McGuffins only space can give, and we need.
I beg you to refute my points, for I'm sure they are flawed.
A really funny economics lesson is here: "http://www.youtube.com/watch?v=d0nERTFo-Sk
The essential lessons to draw from this are Keynes had it backwards, animal spirits are active all the time, but as Hayek says; easy money or low interest rates provide the tools for malinvestments (or for our purposes investments in space). This theory isn’t too far out from our experience; LBJ used the Space Race as a means of doling out megabucks to industrialize the South. More typically the “pols with machinations” get their hands on the money and send it to non existent Congressional districts (Canadian readers will recall the “Billion Dollar Boondoggle” and “ADSCAM” where huge sums of money was paid out to contractors for little or no work).
McGuffinite may be a physical item like 3He or water, it may be energy from the Sun or the magnetosphere of Jupiter; or it may be an idea like creating a location free from interference to achieve you own religious, social or economic goals. These have all been done in our own history (the settlement of the New World was a series of attempts to find McGuffinite or create New Jerusalem, followed by the discovery that the “real” McGuffinite was something quite different and that New Jerusalem isn’t achievable on Earth. Of course, by this time there are lots of people who arrived for one purpose, but no longer have the means or desire to return home.
So it looks like the best way to get into space in a big way is to inflate a bubble and have investors chase the illusion of high returns for Space Tourism, 3He mining or whatever else strikes your fancy. Infrastructure will be created, and a cadre of trained personnel will be in place to support the space infrastructure. Once the bubble pops, all this will be available for a very low price, and some investors will snap it up in an attempt to chase higher returns (“Well, no one has tried to get Deuterium from NEO’s yet. The delta V is lower than getting to the Moon and the equipment is already available…) recreating the cycle. (This even plays into a trope I brought up earlier; people moving into abandoned or underutilized infrastructure for a short term “Road Warriors in Space” scenario, heh)
Thucydides:
"So it looks like the best way to get into space in a big way is to inflate a bubble and have investors chase the illusion of high returns for Space Tourism, 3He mining or whatever else strikes your fancy..."
This is essentially what happened with Iridium. THe original investors got cents on the dollar, but the current owners seem to be making a reasonable profit. Problem is, it turned off large scale space speculation for probably a century.
Space tourism seems to be the biggest potential space bubble in the near future, while speculation in things like space elevators, SSTO spacecraft and other speculative tech provides the seeds for other bubbles
How big these bubbles could get depends on lots of other factors (many of which might be hard to quantify; who would have considered Tulip bulbs to be the object of a massive bubble?) so the "Space Bubble" that finally gets people into space in a big way will be pretty unexpected to most observers.
In the anime Mobile Suit Gundam Wing, humanity has placed massive space colonies at the Lagrange Points. That's one of the reasons I like the show, because colonizing the orbital space around Earth is a lot more realistic than colonizing the Moon or Mars. It can be easily done, as the ISS has proven.
Infact, I can imagine living in an orbital habitat easier than I can imagine living on an inhospital world like Mars. For a place like the Moon or Mars, it'd be best just to drop automated factories and worker droids on the surface and have the resources launched up the well to the orbiting colony.
Just look at what Bigelow Aerospace plans to do in the next few years. Very exciting stuff!
Hello, All, long-time lurker, first-time poster here. Had a few thoughts I figured I might throw out.
Firstly, re: Rick's observation on mining Saturnian McGuffinite, should such a thing ever be discovered: “It will involve the necessary minimum number of humans in space, especially Saturn space; from every operational perspective the optimum is zero.”
I'm not so sure about the optimum being zero. Automation is very good – when it works. My day job ( I say day, though, actually, I mostly work nights) is as a systems operator at a largely automated facility. The system monitors its own operation quite thoroughly, and is even capable of messaging someone at home when something goes wrong with it, including a description of what has gone wrong with it. Which, ultimately, means that if everything were always optimum, I'd be kinda superfluous. Except – when something does go wrong, it usually goes spectacularly wrong. To the extent that its cheaper to pay me to sit in a control room on-site and read this blog all night waiting for something to start beeping an alarm than it is to remediate the amount of damage done in the time it takes someone to get there from off-site. In fact, the difference in insurance premiums is pretty much enough to justify my job.
When the “site” is a multi-trillion-dollar McGuffinite extractor thingamajig that's months away from the nearest on-call technician – and hours away from even being able to let someone know that something is wrong with it – I think you'd want at least a skeleton crew on-site, despite the logistics issue with keeping them supplied. Hauling crew and supplies out every so often is probably cheaper than hauling a whole new thingamajig out every so often.
Secondly, if we're going to all this trouble to begin with, McGuffinite must be pretty valuable. I mean, REALLY valuable. If I'm loosing a million dollars of production a day because a machine broke down and needs a ten-cent screw that's still fifteen weeks out, I'm also going to look real hard at what it would cost to set up the infrastructure locally to make that screw. If its less than fifteen weeks X seven days X a million dollars, I'm probably going to make the investment. Now we have the beginning of a local-space infrastructure, even if its only little. And hey, when that plant isn't making my new screw, it might as well make something else, no?
Of course, this assumes McGuffinite to begin with.
--Rumrunner.
Also, Citizen Joe made an interesting observation about Kansai International Airport that got me thinking about Japanese infrastructure spending, which is an interesting topic in and of itself. The Japanese government – indeed, many governments, especially those struggling with certain types of difficult-to-solve problems – has a fondness of economic stimulus plans that involve generating jobs through vast infrastructure projects (such as reclaimed land) that, ultimately, don't really pay off in terms of sustained returns. That is to say that, yes, they employ a lot of people at the outset, but when the project's done, those people are unemployed again, and the finished project itself is under-utilized because there wasn't really a need for it beyond creating jobs in the first place. Consequently, it doesn't ever generate enough residual economic impact to offset that loss. So, the government comes up with a NEW infrastructure project to employ those people again.
I could see space being developed in a similar fashion, too. “Oh, crud, we've finished the moon-base, that we don't actually need, and that leaves twenty-thousand people out of work at the Earth-side factories, and there's a midterm election in six months. Uh... Uh... quick! Let's vote to build a Mars base.” I mean, just look at all the Senators who fight to keep various projects alive if they bring money to their constituencies, regardless of the actual usefulness of those projects. Once you've built that infrastructure, it will come to SOME use, and it will continue to be supported on some level because of the need for maintenance and such. Not necessarily good for national economics, but it could get us a foothold infrastructure built in space before we actually need one – and therefore make it easier to reach the point where we do need one.
Or maybe that's just wishful thinking.
-Rumrunner.
And this is why I like Star Wars. 25,000 years of technological advancement, space travel is as easy as breathing.
I think the only way to get large groups of people enough to have a rocketpunk scenario is that someone forces them. A dictatorial regime that for some reason decides sending dissidents to space is better than deal with them on Earth, a ecologist government that wants to get as much humans off Earth as possible, etc.
Example: In my story, the all-powerful AIs (think of the Archai from Orion's Arm) decide that biological life, since it created them, is the most important thing in the universe. So after FTL is invented, they go in a frenzy to terraform and seed planets with life both terrestrial and alien. They also try to get as many people out of Earth and the Solar system as possible, so they take landless nations, religious groups, corporations, rocketpunks like you and me, and basically anyone who wants to live in space, to have a "backup" that could restart AIs if something happens. A couple of millennia later, humans and lesser AIs are left to their own devices, and start to build their own states and empires on the terraformed worlds, and a star-trek like civilization appears.
Is it possible? Not likely. Is a LITERAL deus ex machina? Heck yeah. But is a nice way to sidestep the slow colonization and have a galactic civilization in a couple of millenia, unlike realistic prediction that say that we won't colonize the nearest stars in 2000 years. Just replace "All-powerful AIs" with something else (God, aliens, secret society, dictatorship...) and adjust the scale (centuries instead of millenia, the solar system instead of the nearest stars...) and the motive (protect life, exile unwanted people, money...) and there you go!
Note: A bad writer would just use the excuse that I wrote above to justify his/her rocketpunk scenario and that's it. A good writer would not leave it just as a excuse, but would explore the implications. By example, were those the AIs true motives? What did the humans think about this sudden change? Was there any resistance? And more important: What were the consequences in the time where the story is set? A reader would ask all these questions, and is up to the writer to provide interesting and sensible answers.
Scientists are already in space exporting knowledge down here, the reason we don't go to the Moon anymore is because there is nothing there left to see
ummm, no. We don't go to the moon anymore because there's no immediate (not even foreseeable) financial or political gain to be had. There would be TONS of science to do. The apollo missions didn't really do much research, their staying time was too short (after all, they were intended to be followed up by a moon base).
So, there's tons of stuff left to see on the moon. Just nothing that anyone would pay huge sums to see.
The Caribbean sugar islands have come up before - under "On Colonization," I believe. Rick's Antarctica comparison got me to thinking of the Hudson's Bay Company. Which, early on, did lead to some saber rattling and the odd bit of shockingly expensive defense infrastructure in the middle of absolutely nowhere:
http://en.wikipedia.org/wiki/File:Churchill_Fort_Prince_of_Wales_1996-08-12.jpg
Rumrunner:
"economic stimulus plans that involve generating jobs through vast infrastructure projects (such as reclaimed land) that, ultimately, don't really pay off in terms of sustained returns"
These are stupid. If you want to pay people for doing nothing useful, then just pay them for doing nothing. Don't waste resources on a job that doesn't need to be done.
Fernando:
"FTL is invented,"
Well if you have that, you don't need to reach for such hard excuses to explore space. The objection to space travel is that it's way too expensive for anything that might be gained for it, and that anywhere worth going takes forever to get to.
Of course, you also need terraforming in addition to FTL, which is nontrivial (as the current lack of flourishing gardens in Antarctica shows). It will, however, surely be orders of magnitude easier if we can actually move our equipment into position.
Welcome to a couple of new commenters!
Just a quick drive-by comment for now ... carry on, everyone!
FTL doesn't have to be invented, just proven possible. But not for the sake of US traveling but rather for defensive reasons. If FTL is possible, then someone else or something else might invent it and use it for travel, potentially to Earth. We would need to be ready when that happens. That means we'd need research in order to figure out the 'rules of FTL' and then place hedge forces at key locations, just in case. Once those forces are in place, and the infrastructure to support them is set, the system can be subsidized with commercial interests. That gets us the cheap(er) launches and facilities, plus it puts warships in space.
Milo said (in response to rumrunner):
"These are stupid. If you want to pay people for doing nothing useful, then just pay them for doing nothing. Don't waste resources on a job that doesn't need to be done."
Yes they are. They are also real examples that have occured over several decades and in several countries...so, yes, as silly as it sounds, this could actually happen.
Milo said:
"So, the scientific research excuse again. We don't know what we'll find but we're sure there must be something interesting."
Ummm...no. It is the prospectors/explorers/conquitodors trope ("by God, I know that there's gold/oil/uranium/pepper/salt/etc somewhere around here and I'll find it or die trying!"; please don't confuse the one with the other, someone might get the mistaken impression that you aren't paying attention ;)
Ferrell
-Milo
These are stupid. If you want to pay people for doing nothing useful, then just pay them for doing nothing. Don't waste resources on a job that doesn't need to be done.
When has that ever stopped anyone? Governments like to get some sort of benefit from expensive pork barrel makework projects- say, a highway, or weapons or something. Sometimes the fact that it is not profitable is the incentive for the government to do it. Again think about interstate highways or rural electrification infrastructure. These things are too expensive to be appealing to a private company. But a perfect government project.
Besides, history is full of expensive boondoggles that seemed like a good idea at the time, especially when it’s a religiously motivated boondoggle. Pyramids, cathedrals, temples filled with gold and riches… all of which are quite expensive.
Don't forget, there doesn't have to BE aliens with FTL ability, just the possibility of their existence. Create a partially credible fear of something and tax payers will drive truckloads of money up to your doorstep to protect themselves against it. That fear only needs to last long enough for capitalism to take hold and make use of the unknown.
The BuReloc trope of transporting convicts, political prisoners or undesirables to Botany Bay isn't going to happen for the simple reason that it is far cheaper to liquidate these people right on the spot.
The 20th century is the record holder for this sort of behaviour (the Chinese Communists are thought to have the record of exterminating 60 million human beings under Mao, the USSR under Stalin coming a distant second with 20 million and so on down the line...), although groups have suffered persecution and massacre throughout history.
Transporting prisoners made a certain amount of sense when there was a need for unskilled labour in the colonies, but it is a bit difficult to make that case for a space colony or surface installation (unless you propose to transport aerospace engineers, computer programmers and PHD's in assorted disciplines).
This works in the space setting as well, colonists are likely to space dissenters under authoritarian regimes (or recycle them into the biosphere) rather than transporting them to the Libertarian space colonies...
I will make one defense of McGuffinite in terms of literature: it considerably eases the social and political speculation.
Yes, we can speak of five hundred or a thousand years hence to have our populous space colonies, but that requires an extra three to eight hundred years of political, social and linguistic speculation, not to mention accounting for all the earthbound technologies we may accumulate in that time and all their spillover effects.
McGuffinite allows the author to work within the next two hundred years, which is much easier to pin down (not easy, mind you, but easier). After all, much of the Rocketpunk future we could have if not now, then soon, if only we could find the money. Having something profitable to chase in space lets an author keep the social milieu closer to home (and her audience) while providing the spaceships and colonies required.
I'm sure there's a corollary of Bunside's Zeroth Law for this. Rick?
There's also the bonus side-effect of skipping the "will we still be in any condition to launch a massive space effort in a thousand years" question.
[Edit: damn Blogger and its lack of editing.]
Thank you Raymond! I was about to say that.
It comes to the point, where we can say "we can't do this and we can't do this..." and sometimes we can alter the setting and scrap a trope or two.
However, it seems to be getting to the point on these discussions that we are edging the concept of space travel itself completely out of reality. Of course it would be nice tohave a completely realistic setting... but that seems to be so hostile to rocketpunk as to be an existential threat.
Ergo, realistic space travel is no space travel.
Can we try and do abit of "handwaving", just once, pretty please?
Just some social economic handwaving, not technological. Otherwise, its no rocketpunk for you.
Citizen Joe:
"FTL doesn't have to be invented, just proven possible. But not for the sake of US traveling but rather for defensive reasons. If FTL is possible, then someone else or something else might invent it and use it for travel, potentially to Earth. We would need to be ready when that happens."
If I proved FTL is possible, that would not mot motivate me to invest further in STL space travel. That's like going "Oh no, we're about to be attacked by a fleet of ironclad warships! Quick, build more canoes!". Even if I could salvage some cannons from an enemy warship, I'd mount them on coastal batteries, not canoes.
Far better to invest in surface-to-orbit defenses until we gain the ability to face the FTL users in their own domain. Even if lower-tech than our aggressors, Earth is a fortress. A cobbled up colony on Rhea won't be. There are advantages to concentrating all your forces in one place. (If you want backup against total planetary destruction, just keep in mind that having their populace spread across many cities didn't save Japan in WWII.)
Thucydides:
"Transporting prisoners made a certain amount of sense when there was a need for unskilled labour in the colonies, but it is a bit difficult to make that case for a space colony or surface installation (unless you propose to transport aerospace engineers, computer programmers and PHD's in assorted disciplines)."
Well, we were talking about shipping out social undesirables, right? ;)
Raymond:
"I will make one defense of McGuffinite in terms of literature: it considerably eases the social and political speculation."
It's considerably more fun to have multiple economically valuable resources, though, rather than just one thing that does everything. And remember that trade requires both sides to have something worth trading.
In the special case of helium-3 MacGuffinite, there a more important reason why it's so popular: fusion power justifies not only the reason why we went into space, but also the means by which we did so. We need a major advance in energy technology for practical interplanetary travel to become plausible, and it just happens to be a convenient coincidence that one popular proposal uses fuel found primarily in space, in small amounts near us (Luna) and in larger amounts farther away once we get there (gas giants). It's two plot lubricators in one.
"There's also the bonus side-effect of skipping the "will we still be in any condition to launch a massive space effort in a thousand years" question."
I am confident that someone on Earth will be, although it may no longer be the same nations that are powerful today.
The only other McGuffinite which exists is the sudden introduction of practical Magitech. I read a small piece in the Technology Review newsletter a while ago which suggested there is a possible analogue between gravity and electricity, including the possibility of creating devices like transformers to modify the force or effects of gravity.
While I am probably butchering the thrust of the article (truthfully, I was having some difficulty understanding exactly what the author was getting at. Gravitational transformers?) let us assume for a moment that Dr Manhatten, Ozymandias and their minions have indeed discovered a practical means of doing this.
There is now a much lesser cost barrier to getting into or moving around in space. Visionaries quickly put together projects and proposals, while investors previously put off by the huge up front costs of space infrastructure and miniscule ROI now find reasons to put money into the enterprise.
The spacecraft and orbital calculations are different but much of what we think about as space industry and colonization tropes can remain or even be amplified by the ease of space travel due to Magitech. Other potential Magitechs can include high density energy sources, the practical manipulation of space/time, wormholes or the Higgs field (canceling inertia would be the ultimate Magitech). "The Gods Themselves" is an interesting book since the introduction of Magitech both starts and resolves the plot.
When has that ever stopped anyone? Governments like to get some sort of benefit from expensive pork barrel makework projects- say, a highway, or weapons or something.
I think Highways are a poor example, since they usually do loads of good to your interstate economy. The arms industry, however, would be a fitting analogy, and oft repeated during history.
I have often wondered if the space industry would not indeed be a logical choice for big term economy "make work" programs. The arms industry is in on the topic big time, quite a lot of statesmen seemed to have had the strange idea that using their unemployed population to manufacture tons of weapons, gaining both admiration from their now working populace as well as power and bragging rights (at least in the short term) in the international realm (most (in)famous example: Hitler).
So it wouldn't really be so off-hand to imagine a more peacefull leader to pull of the same trick by conquering space instead of neighbouring countries, especially in our time where war has become an equally unprofitable (and potentailly even more expensive) activity as space exploration.
These are stupid. If you want to pay people for doing nothing useful, then just pay them for doing nothing. Don't waste resources on a job that doesn't need to be done.
I have to strongly oppose this statement for other reason as well. First, since when has spaceflight become useless? Agreed, we can't expect any MONEY from it, but the scientific gains waiting out there are TREMENDOUS. Alas, as it looks, none of it can be turned into money too easily, so I guess the effort isn't self sustainable in the long run. But that doesn't make it useless!
EVEN if it would be useless, it is still better to employ people doing useless stuff than to just support their needs without them having to do anything for it. I'm working in social developement, and there were some quite tough lessons learned in that area through the last few decades. One of them goes that if you have a larger population group on "first aid" (what we call giving people food, clothing and shelter so they don't die, i.e. having them utterly depend on you for their survival) for a period of six months, you need DECADES (one generation at least!) to transform them back into a working, productive society. That's right, if you have a larger group on the life line for half a year, you ruined a whole generation. They'll never want to work again. It certainly is better to employ them doing useless stuff, even if that costs you MORE than just providing for them. Otherwise, there's no hope of getting the economy going again in any usefull time frame.
Re: Gravity vs. Electricity. Much of the formulas and effects of electricity have a comparable analog in gravity. What is missing is the gravity analog to induced fields, i.e. a wire carrying a current will induce a current in a nearby wire. If the analog holds true, that means that a gravitational body will induce a gravitic field in a nearby body. Now this is either a "DUH! that's what gravity IS!" or (my theory) that gravity is the induced field of all that dark matter we can't find.
Jedidia:
"I think Highways are a poor example, since they usually do loads of good to your interstate economy. The arms industry, however, would be a fitting analogy, and oft repeated during history.
..."
Riiight. The social utility of weapons -- and training men to use them, let's not forget -- is never security. It's always just a waste of resources, because war is BAD. Well, war is bad -- worse than you can imagine if you haven't been there. But it's not the worst thing, and that's why people build weapons. Calling it makework is simple ignorance.
"...but the scientific gains waiting out there are TREMENDOUS."
1. Stop SHOUTING.
2. Scientific return doesn't justify trillions of dollars. Sorry -- that's just the way the world works.
1. Stop SHOUTING.
sorry. Was more thought as an emphasis.
Riiight. The social utility of weapons -- and training men to use them, let's not forget -- is never security. It's always just a waste of resources, because war is BAD.
I think you missinterpreted me quite a bit there. I'm not a proponent of said strategy, I merely pointed out that it was used several times throughout history. And that's why I think pumping the resources, if you already have to waste them, into spaceflight would be a more sensible alternative. And one that might even bring gain in some form.
2. Scientific return doesn't justify trillions of dollars. Sorry -- that's just the way the world works.
Which is why we are not doing it, after all, I'm aware of that. As I said, we can pretty much forgett that we will have monetary gain from it (the chances are still higher than when going to war, though). All I was saying is that it isn't useless, and that someone ivesting into it might gain rewards that are economically not really relevant, but still far from being of no value. I'm not saying that anyone would trade all that money for that knowledge, but if you already have to spend your money to make the economy go, you'll get at least something back this way.
Jedidia:
"I think you missinterpreted me quite a bit there. I'm not a proponent of said strategy, I merely pointed out that it was used several times throughout history."
No, I don't think there's that much misinterpretation involved, because AFAIK, nobody in history has ever built weapons just to use up labor and resources. Even Hitler had a purpose for building up German arms, as the world found out soon enough. The effects on the German economy were a side effect, not the purpose.
I laugh at your capitalist historical parallels and puny logic. While you lesser nations debate, my glorious Republic is preparing 100 heavy lift rockets bound for the moon. The Lunar Revolution will be talked about for ages to come. Already I have magnanimously permitted your UUNN inspectors to confirm that my rockets have only peaceful intent and trajectory. Your Anglo-European Defense Council has refused to fire on craft carrying civilians. I will found a Lunar Dynasty that will last 10,000 years. You may continue to debate your economics and rational state-craft.
Most Gloriously Yours,
Comrade-Emperor of Indo-Siam
Barring the pccaional weather satellite (ansd there are porbably too many of them any way due to unnessary duplication) there seems to be absolutely no advantages to space whatsoever...
Fine, handwaving it is.
Ugh,my keyboard is going haywire, sorry about the typos.
Welcome to a couple more new commenters!
My internet access remains very limited for the nonce, so not much more than another drive by comment.
The economics subthread deserves more comment than I can give it, but I will argue that 'make work' is a very relative thing. I'll try to discuss that at more length sometime without sidetracking hopelessly into contemporary political debates, for which there are plenty of venues without this blog.
A commenter asked about the time scale - an interesting question. A good deal of classic SF is set in quite remote futures.
More in the quite near future!
The advantages to space are near-limitless energy, material resources and, well, space. The disadvantage is that you have to pretty much build the land you live on.
When the Comrade-Emperor of Indo-Siam points his rockets at the solar system in a bid to expand his realm, who wants to take the chance that he'll succeed, securing his country's and culture's place as the greatest superpower ever seen?
Space to live and work under your system of religious, social or economic organization without being disturbed by the nosy parkers next door has been a powerful influence throughout history (and perhaps the driving force behind the settlement of the New World and the United States in particular), but if those "masses yearning to be free" can't pony up, or a wealthy sponsor isn't available, then this trope is also a dead issue. (Of course, wealthy sponsors taking people into indentured servitude might have something going for it; you WILL have to stay in the space mines/factories for quite a long time to repay $20 million principle...)
For now, energy is available in the quantity and price we are able and willing to pay, so the theoretical advantages of setting up shop in Solar economy of cis lunar space, the Jovian magnetosphere or the orbit of Uranus to mine 3He is not compelling enough to spur people out there.
This is an interesting point, because if we get priced out of the energy market by accident or design, we actually won't be able to strike out into space to gain access to energy. Most peasant farmers have little surplus after the day to day expenditures of labour and energy required to stay alive for one more day...
Even Hitler had a purpose for building up German arms, as the world found out soon enough. The effects on the German economy were a side effect, not the purpose.
Certainly. Hitlers Buisness was not industry, it was war. Which is what I was trying to say (please be patient while I try to rephrase, english is not my first language):
Hitlers major goal was gain through conquest (or maybe he was enough of a lunatic to not think about gain, only what he perceived to be neccessary, it doesn't really matter. He had supporters that certainly were after gain through conquest), which, as they should have known from world war 1, is almost hopeless.
However, the country was humiliated and economically ruined by the versaille treaty and the reparations, so they had to give the population something to jump on the band wagon. This something was, of course, weapon manufacturing, since it would give the economy a boost, make the people happy and at the same time facilitate the planned war effort, of which no real gain could be had in the long run.
Now, is it so hard to imagine that a more peacefull leader would do the same, just with spaceflight rather than with war? He might even be similiarly nuts as Hitler, just dreaming the more peacefull dreams of securing his people's glorious future in space rather than establishing them as a ruling race on earth. If the population is desperate enough, they will gladly go along with the vision, as long as it feeds their stomachs.
Of course, it is a completely different question wheather that nation can gather or buy the know how to actually get anywhere significant in the rather short timespan the artificial economic boom is sustainable.
There are hidden expenses to our energy production, like storing depleted uranium and excess greenhouse gasses, not to mention depleting the natural resources in the first place. And as the population increases, so too will our energy requirements.
Start with this premise. Assume that suddenly you couldn't use fossil fuels anymore. No petroleum products and no coal. Maybe we run out suddenly. Maybe something causes that stuff to be super toxic to humans. Maybe we've pushed to world to an environmental edge. At that point, we've got a limited supply of energy and need a means to solve the energy crisis.
Jedidiya:
"Now, is it so hard to imagine that a more peacefull leader would do the same, just with spaceflight rather than with war?"
It's impossible for me to imagine such a thing. Space operations require resources, knowledge, and skill. If you have those in large enough supply, you won't be having serious economic issues, except those due to the business cycle. And nobody is going to try to reverse a temporary economic downturn by committing to trillions of dollars over decades for pie in the sky.
This kind of thing in general is the problem with MgGuffinite space futures. In order to get to the McGuffinite out in space, you have to be economically and technologically strong enough that you probably don't need it.
Tony:
"This kind of thing in general is the problem with MgGuffinite space futures. In order to get to the McGuffinite out in space, you have to be economically and technologically strong enough that you probably don't need it."
You may not need it, but you may very well want it, and badly.
The usual SF McGuffinite has much in common with oil, simply because that's what authors are generally familiar with (and often want to write perilous warnings about). The oft-cited tipping point for oil as a fuel source was when the Royal Navy decided to switch from coal; there were strategic problems, but it won out. A generation later, practically everything ran on it, and we're off to the races.
D-He3 fusion technically has some similarities to oil: better power and energy density than competing sources, large reserves far away, smaller reserves close by, even an analogue to the Fischer–Tropsch process (He3 production by means of tritium decay).
For a given McGuffinite, you may not need it at the beginning, but you may end up needing it down the road.
At that point, we've got a limited supply of energy and need a means to solve the energy crisis.
There are lots of historical examples of this happening, the shift from charcoal to coal, whale oil to mineral oil and oil to electricity. Human inginuity will rapidly come up with an answer (probably commercializing a technology which is currently not economical like geothermal or OTEC, or creating a synthetic hydrocarbon fuel)
If this isn't done quickly, most of the Earth's civilizations will sink to a peasant farming level, which is SF of sorts, but not Rocketpunk.
Citizen Joe:
The scenario you described is already happening here and now, prehaps a bit more slowly. And guess what? Nobody (important, at least) seems to care. Why a reader would expect the same in a sci-fi story?
Also, the current methods of launching rockets consume too much of precious fossil fuel for that plot device to work. I think that given enough time a money, one could devevolp a rocket that works on biodiesel, but that money would be better used to devevolp cars and other fuel consuming stuff used by most people.
Back in the 1950's, the "McGuffinite" was geosynch communication facilities and orbital weather observation. The difference was: transistorized electronics had not been invented, so these valuable items would have to be provided by manned stations.
The same would hold true for NASA planetary exploration: no robots means astronauts.
Amusingly enough, this appeared in the game GURPS: Lensman. In order to create a time line containing Lensman, Mentor of Arisia altered history so that the Bell lab scientists invented the Ultrawave tube instead of the transistor. Can't have Lensman with crutches that created flabby lazy minds (things like pocket calculators, spell checkers, and Google)
nyrath:
"The same would hold true for NASA planetary exploration: no robots means astronauts."
Exploration is actually one thing that humans still do better than robots even once robots have become available. (Robots are good at routine and predictable tasks. A research vehicle, however, is almost per definition expected to run into unexpected circumstances. If it doesn't, is isn't doing its job right.) We're using robots rather than astronauts because putting astronauts on Titan is way too difficult, expensive, and slow.
So whether or not we have robots, we'll still be sending astronauts to other planets when it becomes viable. The difference is that thanks to robots, we can do some preliminary exploration to bide our time until that happens.
There are hidden expenses to our energy production, like storing depleted uranium and excess greenhouse gasses,[pedant mode]
depleted uranium is the stuff you have left over after you get the good fissible fuel (U235) out of raw uranium (pitchblende). U238 is less radioactive (primarily an alpha and beta emitter, iirc) than U235, and is not particularly toxic unless ingested. Not any more toxic than mercury, anyway, and we use tons of *that* on a daily basis.
Let's be really serious here: In the 60 years since nuclear fission power production started, the total volume of spent fuel (the really dangerous stuff they call "high-level radioactive waste") is roughly equal to 100m by 50m by 3m. That's not just from the US, that's from all countries with a nuclear program. If the US still reprocessed fuel, it'd be about a third that size. The problem is that reprocessing fuel is associated with weapons programs, since the primary usable content of high-level waste is actually Plutonium (which isn't particularly usable in most reactor designs).
The greenhouse gas problem is a far bigger priority.
Raymond:
"You may not need it, but you may very well want it, and badly.
The oft-cited tipping point for oil as a fuel source was when the Royal Navy...
D-He3 fusion technically has some similarities to oil...
For a given McGuffinite, you may not need it at the beginning, but you may end up needing it down the road."
The problem with that analogy is that the RN went everywhere in the Eastern Hemisphere on coal decades before it converted to petroleum. Before that, Europeans went to those same places on wind power for a couple of centuries. So petroleum was hardly a McGuffinite.
The actual McGuffinite for long range navigation was East Indies goods -- primarily spices -- combined with a desire to get to them without going through the circumcised dogs that traduced the State. But there isn't anything in space that we know of that we can't find here, and nobody has such tight control of any commodity market that going to space for it would make more sense.
Fernando:
Also, the current methods of launching rockets consume too much of precious fossil fuel for that plot device to work. I think that given enough time a money, one could devevolp a rocket that works on biodiesel, but that money would be better used to devevolp cars and other fuel consuming stuff used by most people.
Just a note: It’s perfectly possible to launch without fossil fuels or indeed hydrocarbons of any kind. Hydrogen is a great rocket fuel, is nonpolluting (exhaust is water vapor), and has virtually unlimited availability. It’s harder to work with than, e.g., kerosene, and so carries engineering penalties (i.e., more weight). But it’s not at all impossible and given advances in structural materials that make the weight penalty less severe it may well turn out to be the propellant of choice.
Rick recently suggested that $100 billion might be the amount needed to get the ball rolling. The question of why on (or off) Earth anyone would spend it has brought comparisons with defence spending and public infrastructure projects (both useful and make-work).
What about charity?
Stop laughing, please.
I was just struck by the fact that the combined wealth of the world’s two richest men (Bill Gates and Carlos Slim) is on the order of $100 billion, with Warren Buffet also weighing in at near $50 billion. I don’t know about Slim, but both Gates and Buffet are into philanthropy; the Gates Foundation already has an endowment of some $30 billion, and Buffet IIRC plans to give the bulk of his fortune to it on his death.
In other words, a foundation with $100 billion to spend is not as crazy as it sounds. What if the next generation’s Gates or Buffet, raised on a diet of great nouveau rocketpunk literature, left his wealth to a foundation whose charter was to get humanity into space for real?
How about an airborne bacteria that was designed to capture CO2 and CO emissions from cars and then release beneficial exhausts in an attempt to save the environment. However, an unforeseen side effect was a mutation released cyanide gas as a byproduct. This problem doesn't become noticeable until it is too late, the bacteria has already carved itself into the ecosystem.
I'm going to assume that the problem occurs at high temperatures and pressures, so forest fires aren't (more of) a problem. Now that being said, I'm sure that properly filtered and sterilized air would alleviate part of the problem, but it would be completely unwieldy to filter the air required for a car. Likewise, using straight oxygen (no atmospheric nitrogen) would work by starving the bacteria of its nitrogen reactant. Again, an impractical option.
Is that a plausible McGuffinite? Rather than something to find, it is something taken from us. That is a rather nightmarish scenario involving a fairly catastrophic crash of the ecosystem. Could you imagine a bacteria colony reaching critical mass during a traffic jam in NYC or on the freeways of LA? All those dead people at the wheels with their engines churning out tons of toxic gas.
tkinias:
"What if the next generation’s Gates or Buffet, raised on a diet of great nouveau rocketpunk literature, left his wealth to a foundation whose charter was to get humanity into space for real?"
Any trustees trying to act on that charter would be immediately tied up in court by people who wanted it for "real" charity, and kept there until they found a loophole through which to renounce the charter or re-obligate the funds. Or a government would just declare the charter illegal and take the funds.
Before you go there, don't tell me that all of the money is sent right here on Earth. That kind of spending goes to benefit educated, relatively well-off engineers, technicians, and administrators. It's the poor we have to spend our surplus on, dontcha know?
Citizen Joe:
"How about an airborne bacteria...Is that a plausible McGuffinite?"
Nope. It would kill precisely the people who would be needed to save the race.
Citizen Joe:
"Rednecks with 4x4's?"
Uh-uh -- anybody with a car or who lives near cars, which is just about the entire educated population.
That's the catch with the environmental-disaster-to-space trope: You have to imagine something so devastating that people would actually prefer to live in space, yet something so slelective that it doesn't kill the millions of people that are needed to move even a small fraction of our society off-planet.
@Tony:
If you had to write a Rocketpunk setting, what would be your "ball rolling" substance/moment?
Please noe I said substance. What would get us into space in your setting?
p.s.: charities don't quite seem so impossible as an idea... they are not scientifically implausible, and don't involve any danger to the population...
Just a thought.
Re: Geoffrey S H
I wouldn't assume an inflection point. I'd figure on steady development, expanding the off-Earth population by an order of magnitude every century or so: 100 by 2100, 1,000 by 2200, 10,000 by 2300, and so forth. The very highest rate of increase I could imagine would be maybe an order of magnitude every fifty years.
I'd just live within that constraint. My surface-orbit rockets would be chemical. My interplanetary propulsion would be solar/nuclear electric.
Now, I know it's not a popular opinion, but it's an equally valid one within the context of this topic -- I simply don't believe in McGuffinite.
The cyanide bacteria wouldn't kill everyone immediately Yes, there would be massive deaths in the big urban centers, but the smaller cities would have more warning. So you'd get the horror factor of birds dropping out of the sky first, with some research going into it (or at least a committee formed to address the issue at the next meeting). Then sudden deaths at street level and claims of a terrorist attack. Then more outbreaks in other congested areas. Then a partial black out as the people running the coal fired power plants all die, allowing the plant to overload. Discovering the cause could be tricky, since the bacteria only causes problems under specific conditions. All CDC could tell is that cyanide is being released in high traffic areas. As the cyanide levels start spreading out to include lower and lower traffic areas, emergency actions would be taken to limit vehicles to emergency vehicles only. Eventually the cause gets found and there is a lot of finger pointing and many attempts to bypass the problem. But the damage is already done, short of complete sterilization of the entire biosphere, we'll never be safe using hydrocarbon fuels again.
So there you go, world wide, oil and coal are suddenly not options for energy production. Assuming we don't do something silly like conserve energy, that means we need to find other energy sources. Fission works but Uranium is a limited resource. It is also a controlled resource. While production could probably keep up with demand, there would be a massive amount of depleted uranium to deal with coming out of the refining process. Wind and water power are both options but they are limited use by location. Solar is a moderately good option, but again the day/night cycle could make it non-viable. That makes the orbital solar collectors look good, which would be a kick to get launches going. Cars could be made to run on hydrogen (thus no carbon for the bacteria) but the hydrogen would need lots of electricity (and other power) to be created. The need for electricity and CLEAN electricity will grow, which pushes fusion technology. Once He3 fusion is operational, it is off to the races in space. First the moon is mined for its fuel and some of the processing techniques get perfected in csi-lunar orbit. Next stop is the asteroid belt to get resources there rather than lifting ships from Earth. When you get a D-D fusion breeder reactor operational, you stick it in space to prevent further radiation problems on Earth (D-D fusion throws a lot of neutrons). Now you're making your own He3 with Tritium 'waste'. Use the D-T torches and the outer solar system becomes available for more hydrogen mining. Meanwhile resources from the asteroids prove useful in batteries allowing the car addicted people of Earth some faint glimmer of the glory of yesteryear.
Citizen Joe:
"Solar is a moderately good option, but again the day/night cycle could make it non-viable. That makes the orbital solar collectors look good, which would be a kick to get launches going."
Even at 25% of orbital efficiency -- due to day/night, atmospheric absorbtion, and clouds -- solar power collection on the ground is orders of magnitude cheaper per megawatt than on-orbit collection.
"Once He3 fusion is operational..."
Another technology I wouldn't hold my breath on.
So you want a McGuffin. Well, I’ll give you one.
Insolation control. With all the concern over anthropogenic climatic change, instead of worrying about the mixture of gases in the atmosphere, we could control the amount of sunlight that reaches the planet’s surface. Build a sunshade or a series of shades in orbit or at the first Earth–Sol libration point.
Humans in space would probably be needed to build and maintain this system.
Simpsons did it!
Scott Nov 23 11:49 pm :"The problem is that reprocessing fuel is associated with weapons programs, since the primary usable content of high-level waste is actually Plutonium (which isn't particularly usable in most reactor designs)."
Though the association less real than most people think. Seethis.
Howver, the economics of reprocessing spent nuclear fuel is rather marginal unless & until the cost of uranium risies substantially.
Citizen Joe Nov 24 3:33pm : "Fission works but Uranium is a limited resource."
Less limited than fossil fuels though. The present kinds of reactors that use less than 1% of the energy in the uranium could run the world for centuries. Reactors that breed U238 to plutonium or that breed thorium to U233 could run the world for millions or billions of years.
Energy from space isn't going to be the McGuffinite for a robust space program, because other energy sources, especially fission, are more than adequate. OTOH fission keeping industrial civilization on earth sustainable gives us the time for the slow development of space postulated by Rick & Tony.
The handwaved 'bacterium makes internal combustion engines unusable' idea would create a large market for fuel cells that can run on a liquid fuel like methanol. IINM plausible fuels cells for cars still need platinum group metals as catalysts. I really must find some hard data on the availability of PGMs in earth bound ores & the concentrations in asteroids & asteroid fragments in the lunar regolith to confirm or debunk them as my favorite mcguffinite for space development.
Tony (Re: Citizen Joe):
"That's the catch with the environmental-disaster-to-space trope: You have to imagine something so devastating that people would actually prefer to live in space, yet something so slelective that it doesn't kill the millions of people that are needed to move even a small fraction of our society off-planet."
You also need to have the hazard be sufficiently aggressive that it cannot be vanquished or quarantined on Earth, yet somehow still completely incapable of following you into space. What if some of those bacteria get onto your spaceship? Then what?
M. D. Van Norman:
"Insolation control. With all the concern over anthropogenic climatic change, instead of worrying about the mixture of gases in the atmosphere, we could control the amount of sunlight that reaches the planet's surface. Build a sunshade or a series of shades in orbit or at the first Earth-Sol libration point."
This kind of brute force approach to environment control has a history of messing up on us. Try to fine-tune too much, and you end up in a fragile artificial state where a slight push in any direction spells disaster.
If we do want to reduce insolation, it would be far easier to scatter some dust into the atmosphere or something.
Or, you know, we could just stop making all those greenhouse gasses.
Milo: "What if some of those bacteria get onto your spaceship? Then what?"
Actually it wouldn't matter. The hypothetical reason why the bacteria are a problem is that at high temperature and pressures, they produce cyanide at toxic levels. Under other circumstances, they act as atmospheric scrubbers, reducing CO2 and CO. So, they would be helpful on a spacecraft.
That being said, it is relatively easy to sterilize a ship compared to an entire biosphere. So you could (with reasonable confidence) avoid contaminating another world, thus allowing you to drive IC cars there... not that you would, having developed other energy sources.
I think that the more likely scenario is that don't research new energy technologies but rather the world descends upon itself in an attempt to seize control of what little (safe) power generation is available.
Milo:
"If we do want to reduce insolation, it would be far easier to scatter some dust into the atmosphere or something. Or, you know, we could just stop making all those greenhouse gasses."
The bacteria I described is exactly what you're talking about. Originally, they are just supposed to cut down the green house gasses and spread in the atmosphere like dust... The end result is not good... But that was your point about mucking with Mother Nature.
Citizen Joe:
Under other circumstances, they act as atmospheric scrubbers, reducing CO2 and CO.
Not to be a party-pooper, but this is what plants do (the CO₂, that is). Photosynthesis is the way to go ‒ it’s what got us in the first place from a CO₂-heavy atmosphere to the oxygenated one we enjoy today.
The CO2 scrubbing is more of a plot device which allows the bacteria to survive even without the continued presence of IC engines. Which means you can't just shut down for a while and hope they simply die off. The hypothetical bacteria is only dangerous in large concentrations in the presence of hydrocarbons, nitrogen, high temperatures and high pressures. I suppose that in very dry environments, you could drive down the population by not using hydrocarbons. Humid environments would allow the bacteria to thrive unless local flora out competes for the CO2.
Tony:
My whole point was that petroleum wasn't a McGuffinite at first, but it very much is now.
I'd also give some credit to gold, for driving continued exploration of the Americas once it was well-established that there were no easy routes for the spice trade, and being a proper Canauck, I should mention the fur trade which was easily profitable enough to keep people coming back and forth.
As for the space equivalents of fur, tobacco, sugar or cotton: no idea.
Citizen Joe:
A blight that specific, that forces us to leave without killing us off completely, that changes our economy without ruining it, that seems so curiously tailored, doesn't sound like an accident.
It sounds like a bioweapon.
On space-based solar power:
Solaren is supposed to begin delivering power to PG&E in 2016. From what I've read, the contract isn't yet final, and PG&E isn't assuming any of the risk, but we may have some data points on cost and feasibility soon (if only in the negative).
Oh my... I just did a quick check on world energy usage... Seems that 87% is in the form of fossil fuels (petroleum, coal, natural gas). Of the remaining, it is just about an even split between hydroelectric and nuclear. An insignificant portion is solar/wind/etc. Since hydroelectric is dependent on location and thus unlikely to be expandable, that means building about fourteen times as many nuclear power plants than we currently have to meet demands. That's like 6000 more reactors... That would push the efforts for fusion reactors.
Raymond:
"My whole point was that petroleum wasn't a McGuffinite at first, but it very much is now."
How is it McGuffinite at any point in history? Europeans were making journeys to, and doing business in, places much further away from home than the Mideast, long before petroleum became a strategic issue. The Mideast is really a side trip on the way to the East Indies and Asia. About the only transport innovation it led to was the supertanker, which was just an economy of scale play on existing technologies.
"I'd also give some credit to gold, for driving continued exploration of the Americas once it was well-established that there were no easy routes for the spice trade, and being a proper Canauck, I should mention the fur trade which was easily profitable enough to keep people coming back and forth.
As for the space equivalents of fur, tobacco, sugar or cotton: no idea."
With the exception of gold, those are all commodities that relied on the Western Hemisphere being the same general environment as the Eastern Hemisphere, just with fewer and/or less competitive people to get in the way of resource utilization. Space is an entirely different animal.
"Solaren..."
...is a fraud suit waiting to happen. If they deliver, they'll do so at such a high rate of loss that their investors will have a cuase of action. If they don't deliver, then PG&E will get them.
Citisen Joe:
"Oh my... I just did a quick check on world energy usage...That would push the efforts for fusion reactors."
If it's impossible, it's impossible. Stars require hundreds of thousands of planetary masses to generate enough gravity to cause fusion. Electromagnetism may be stonger than gravity, but there's absolutely no evidence that electromagnetic confinement can sustain a fusion reaction long enough, at high enough energy return, to actually generate more power than is put into the process. We simply may not be able to do it. It's like a lot of other things we think are possible because SF authors dream them up -- just because it's theoretically plausible in an ideal universe doesn't mean it's practically possible in the real one.
Fusion reactors are a form of McGuffinite. If fusion reactors are possible, then they provide the energy for a space economy as well.
This can be indirectly, as the GDP grows and more wealth is available to support projects like Virgin Galactic and prestige science and technology projects like the ISS. More directly, it means that there is lots of energy to do things like make inexpensive rocket fuel and storage parks (fuel is actually rather cheap, huge cyro storage tanks and the material handling equipment to go with that isn't), or going the next step, beamed energy to boost payloads into orbit.
If the fusion reactors are small enough (IEC, Migma, Dense focus fusion, Magnetized Target Fusion, etc.), then they also provide energy directly as the rocket motors (almost the ultimate high ISP drives, especially if you use the reaction product directly as the reaction mass; calculated ISP can reach 1,000,000 for some types of fusion rockets).
Note this does not even look at space as a fuel source; p+11B or Deuterium are common enough on Earth to run a comfortable economy and fuel ships. It is very convenient to be able to pull up to a NEO and extract Deuterium from the ice, or have a filling station at Miranda with a Dewar farm of 3He, but that is an effect rather than a cause in terms of space development.
@Tony: Its alarming that governments and scientists are willing to experiment on fusion or fission/fusion hybrids projects then... and no, it can't simply be handwaved as 'pork-projects" or "politics".
http://en.wikipedia.org/wiki/International_Fusion_Materials_Irradiation_Facility
http://en.wikipedia.org/wiki/ITER
http://en.wikipedia.org/wiki/National_Ignition_Facility
http://en.wikipedia.org/wiki/Nuclear_fusion-fission_hybrid
Not on experiments that extensive and expensive. Unless alot of valuable data on other things can be gathered from them... and I would be skeptical to think that they could not be obtai9ned from more modest experiments.
Now, if they prove fusion to be impossible,fine. I just wouldn't dismiss it right now... not with such a wealth of infrastructure developed. Some scientists can be motivted by "the projct" and lose all hindsight of economy, efficiencey and feasability... but so many?
Hmmm.
p.s: apologies for the wiki articles... not the most accurate, but I'm in a rush and didn't want to get left behind the the conversation.
Finally back to convenient Internet access, and this thread has 94 comments to deal with!
A somewhat meta point. In this series of posts I've been splashing quite a bit of cold water on suggested space techs and concepts. This is by intent. There is a tendency in the space community to treat things that are possible (or simply may be possible) as if they are more or less inevitable.
This has often worked, the Saturn V being the single most conspicuous example, but it also leads to an awful lot of glossing over Step 2. And imagined space futures also tend to gloss over the sheer magnitude of the projected future. Whatever the tech level, grand space futures presuppose a Lot of Stuff that has to be built first.
I thought they got the fusion reactor going for a few minutes. That should be proof of concept that it is possible. But, yes, gravity is a horrible confinement medium.
The more stuff that has to be built, the more raw material for world building and tech developement. Rather ignorant and simplistic of me I know, but its always a good start when world building (with an approach more grounded in science running parralel at the same time).
It porbable we wil eventually get all we want through the natural advncement of tech... but it will be a long time and using technologies we don't even know about. Leonardo couldn't glide through the air, but the Wright brothers and Frank Whittle "could", to a degree and in a way unimagined by a rennaisance artist. Some sci-fi writers don't want to imagine like that... as it often produces stuff too much like magi-tech.
P.s: I sent you an e-mail Rick about books on anti-matter and other stuff... just checking it got through.
Otherwise there are problems with my yahoo account which I will have to sort.
Geoffrey S H:
"Not on experiments that extensive and expensive.
...
Now, if they prove fusion to be impossible,fine."
What they are trying to do is prove that electromagnetic fusion is possible, and at a level of energy output that it can be self-sustaining, with enough suprlus energy to make it a practical proposition for electrical power generation. For fifty years they've been trying prove it. For fifty years now, fusion has been Real Soon Now(TM). AFAICT, it's not at all likely that there will be a success. I certainly wouldn't plan a plausible midfuture with fusion power, even in fiction.
Citizen Joe:
"I thought they got the fusion reactor going for a few minutes. That should be proof of concept that it is possible. But, yes, gravity is a horrible confinement medium."
Gravity plus mass is a great confinement medium. It's success is visible every time you go outside. It just isn't a very practical one at human scales. But there's no evidence that humans can generate sufficient electromagnetic or inertial confinement to sustain a reaction at a high enough energy level that it will generate electrical power for commercial use. To reiterate what I said earlier, just because a science fiction author writes about it -- or even a scientist speculates about it -- that doesn't mean it's possible.
That means that a massive grouping of international scientists have wasted potentially trillions on something that is known to not work.
Words fail me.
Tony:
The point about oil was merely illustrative, and I used the "substance valuable enough to chase hither and yon for it" definition, not the space-specific "reason to accelerate the space presence expansion timetable by an order of magnitude" version. A lot of SF writers use oil as the basis for their McGuffinite, Helium-3 is a common SF trope, and it's interesting that they have such similarities.
That being said, when pressed I'll admit I see D-3He fusion as more useful for space travel than civilian energy production, and thus not a terribly compelling McGuffinite.
Fusion in general, though, you shouldn't be so quick to dismiss. We're hovering around a Q of just under 1 now. ITER is planned to have a Q of 10. JET has given us an extrapolated Q of 1.25 (with a disclaimer: that figure was derived from D-D experiments). The National Ignition Facility has reached the required laser pulse energy, and should give us some nice crunchy ignition numbers as early as next year.
We're past the "coming Real Soon Now, we promise (hands waving frantically)" phase, and well into the "currently building the prototype" stage.
"Solaren..."
...will probably fail hard, yes. But at least someone will have tried, and we'll have the hard numbers to work with. Hard numbers, raw data, and concrete prototypes are always, always better than rank speculation.
"With the exception of gold, those are all commodities that relied on the Western Hemisphere being the same general environment as the Eastern Hemisphere, just with fewer and/or less competitive people to get in the way of resource utilization. Space is an entirely different animal."
And if such a situation ever happens in space, it'll be well past the timeline we're talking about here - barring, of course, McGuffinite.
Geoffrey:
It's not quite that bad. We've already come very close to breakeven with D-T, and we're making progress. Whether fusion power is or ever really will be commercially viable is another question. D-T fusion has neutronicity and tritium confinement issues, and D-3He fusion has ignition temperature and Bremsstrahlung problems. While these issues are large (and I am emphatically NOT attempting to trivialize them), they're less theoretical roadblocks as much as engineering questions.
I wouldn't say the money's been wasted. Not yet, anyways.
Rick:
I think the appeal of McGuffinite is its ability (in literary terms, anyways) to turn a slow burn of expansion into an explosion, thus accelerating Step Two.
I certainly wouldn't plan a plausible midfuture with fusion power, even in fiction.
Well, a later midfuture might be ok. I mean, The problems are engineering wise, not physics wise, it's not like a reactionless drive or some sort of magic. The problem is of purely technical nature, and it is pure speculation to claim that it will or will not be solved. Some ingenious idea might make it work, but genious is not really a foreseeable occurance.
But even if they'd make it work within the next decade, getting the whole thing mature enough for spaceship propulsion would take a while, say the better part of a century. Still, we're talking about far greater horizons here.
And there is of course the very real possibility that we simply can't make it work, at least not with the technology we currently have. So, putting or not putting a fusion drive in a mid-future scenario simply is a gamble: Trust in mans genious to solve the puzzle and put it in, or be conservative and leave it out. Then wait until the end of your life and see if reality proofs you wrong in that time (afterwards you probably won't care very much about it anymore...)
That means that a massive grouping of international scientists have wasted potentially trillions on something that is known to not work.
Words fail me.
Ah, no. If they can't make it work and abandon the project in the end, they'll have invested trillions of dollar to prove that it doesn't work. Which is not what everyone was hoping for, but a valuable lesson none the less. That's just how science works.
Currently, there's still hope. As long as the amount of hope is enough to justify the amount of money, the project will continue. It's as simple as that. And considering the possible gains of the project, even a bit of hope is justification to invest quite some money.
On fusion, in broad perspective the case can be made both ways. On the one hand, after 50 years and enormous expenditure we not yet achieved self-sustainment. On the other hand the time and money have gotten us 90 percent of the way, so that sucker could finally start turning over in about 2016 if we only keep cranking now.
The arguments are not mirror images, which is why debates turn into talking past each other. No proof of technical progress really refutes doubts that an effort that has sucked up so much work will end up practical, any more than the long time it has taken to almost make it work means that it can't work.
So I would call it authors' choice. I would probably have fusion in my midfuture setting merely because fission strikes me as the coal fired steam engine of the atomic age, about as crude and inelegant a tech, relative to its underlying principles, as can be imagined. But for many midfuture settings this is a feature, not a bug.
But so far as providing power for Earth, I think ground based solar including biofuels laps the competition in that race. They are not yet competitive on their own, but the price point is not that high, and continues to come down.
And the stuff is more or less unlimited. Current human energy usage is on order of 0.01 percent of solar energy hitting Earth. Capturing 1 percent of solar energy might be problematic, but 0.1 percent, or 10x current world usage, should be doable, and more than enough for midfuture needs.
Unless the midfuture decides that what it really really wants are SUVs the size of buses going at high subsonic speed. But can that really compete with future generation video games?
Unless the midfuture decides that what it really really wants are SUVs the size of buses going at high subsonic speed. But can that really compete with future generation video games?
And Rick for the win!
Lets face it, even if D+3He fusion was available right now, there would be very few investors with the knowledge and resources to go chasing it or the 3He rush to the Moon and Saturn. Frankly, about 90% of the people would have no idea what you were talking about, and the lure of driving a 747 down the highway at cruise speed would probably outweigh any other consideration (well, almost...)
Checksum. Talk to the people you work with or assorted friends you hang out with at Starbucks (your SF book club and this forum don't count) and see how many of them have an interest or understanding of the topic. Given the sort of people we are and our interests, I'll bet the % of people you talk to who are in agreement is probably much higher than the general public (since we are charming, knowledgeable, incredibly beautiful to the opposite sex and totally persuasive. Or, our friends share some of our interests).
WRT fusion, I'm persuaded we have pretty convincingly proven that magnetic confinement and laser inertial compression are technical dead ends (ITER and its supporting infrastructure is about the size and capital investment of a small aircraft carrier, and laser fusion "labs" which cover several football fields don't represent a convincing model for scaling up to commercial size for investors).
Still, there are lots of other avenues of approach, and it is interesting to me that shoestring operations like Migma have achieved various fusion metrics at a far higher speed and lower cost than the "conventional approach". Google IEC, Migma, Dense Focus Fusion or Magnetized Target Fusion and you will see that there seem to be advances in many directions. Perhaps there is some technical reason or Jesus factor that will make fusion impractical or impossible, but so far as *we* know, fusion is possible by natural law and there should be no reason it cannot be replicated on Earth in a controlled fashion.
WRT energy, the last word should go to Steven Den Beste, who's contributions on "USS Clueless" are still relevant and insightful: http://denbeste.nu/cd_log_entries/2002/09/Obscureenergysources.shtml
including biofuels
Biofuel have a strog economy-ethical problem: First, to shift all fossil fuels to biofuels, we don't have enough soil. Not while we need to eat,anyways.
And while it might be possible to satisfy a fraction of the fuel needs while still having enough to eat for everyone by some pretty radical programs (like, killing most animals and cut down most of the woods), there's still one huge problem left:
Biostuff sold for fuel production will be more valuable than biostuff for food. That means that a lot more biostuff will get sold for fuel than would actually be affordable, and there will be famine. This phenomenon has already begun nowadays: Since a lot of our foodstuffs are already produced in the poorer parts of the world (south america, most prominently) and usually controlled by the rader greedy type of farmers, they rather sell their crops for biofuel than for food, because they're getting more for it. This was responcible for a rather steep increase in grain prices, which wasn't felt so hard in the west, but is a real problem for the third and even the second world.
anyways, This is getting a bit too long and a bit too off-topic. You get the picture. I'm na oponent of biofuel, although I totally agree that we need an alternative to fossil fuels.
Asteroid defence will probably need some sort of small space infrastructure, even if it doesn't get many humans into space...
For now, I will assume asteroids are at least a significant threat.
I think that the biofuel wind is blowing towards algae grown in vats. These can be stored underground and I believe grow better with fiber optic light rather than direct sunlight. Ya, we're probably moving from the information age to a biotechnology age... and yes, you should cringe in fear.
Re: Everybody WRT fusion
Call me unreasonably skeptical if you want, but achieving momentary confinement, or momentary compression, or momentary confinement and compression is very, very far from sustained confinement, compression and surplus power output. We aren't almost there, much less in the prototype stage. There are three possible outcomes, remember -- it can be done, It can't be done, or it can be done but not at an acceptable cost. I can't assign probabilities to these various outcomes, and neither can anyone else. In situations like that, it's likely that the outcome will be it can't be done, or it can't economically be done.
If it could be done, the engineering solution should be obvious. It was only 16 years from the discovery of nuclear fission to the first generation of electricity for civil use by a nuclear reactor. Here we are, 64 years since the first patents were registered for fusion power production, and we don't even know for sure that any of the proposed technical solutions will work. Maybe, just maybe, it's unobtainium.
For those who believe that all of this money wouldn't have been spent if it didn't stand a good chance of working, please consider that maybe it's in the nature of venture capital. But most high-risk/high-reward investments don't pay off. Also, I think that a lot of the money is being provided nowdays out of a combination of special interest inertia and simple fraud. The inertia comes from multiple generations of nuclear physicists basing their careers on nuclear fusion, to the point that the people who advise the politicians about what to spend money on naturally advise fusion research, because that's where many of them made their reputations to begin with. The fraud comes in the form of the advisors not knowing whether they can actually achieve fusion power generation at any level of economic support, but wanting the money, they say they can. Just keep writing the checks, and we'll keep closing in on the objective. All they have to do is show "progress".
That could go on for centuries, or even millenia. All the nuclear physicists need to do is keep asymtotically approaching the goal. Meh.
Citizen Joe:
"I think that the biofuel wind is blowing towards algae grown in vats..."
And it's an interesting question whether you can realize net energy once the energy cost of the infrastructure is accounted for.
Tony:
"And it's an interesting question whether you can realize net energy once the energy cost of the infrastructure is accounted for."
I was under the impression that biofuels were as much or more about energy storage, rather than production (is the same manner as fuel cells). In which case net energy production would be nice, but not necessarily a deal-breaker.
Tony, I don't think your latest fusion post made it to the page (I got it on email). I'd respond, but it wouldn't be fair.
Tony:
Nevermind, there it is.
"...achieving momentary confinement, or momentary compression, or momentary confinement and compression is very, very far from sustained confinement, compression and surplus power output."
Except that the last item (surplus power output) can certainly be had from momentary confinement and compression. Full ignition isn't required for net power. Most of the inertial designs rely on this principle. It's usually cited that a Q value of 20 is sufficient for realizable net power (after system losses). That isn't nearly so far away as infinite Q (self-sustaining reaction). Of your three scenarios, I'd go with "it can be done" or "it can be done, but not economically", leaning towards the latter if you put a gun to my head.
As far as fusion-powered space travel, that's a whole different game, and I'm far more skeptical of that than civilian fusion power generation. Too big, scales poorly, D-T's neutronicity is ill-suited to propulsion, D-3He is too difficult to achieve and has too tenuous a fuel supply. Given five hundred years, maybe; in the next couple hundred, probably not.
Re: Raymond
The fusion post did make it after a while.
WRT biofuels, if you're just looking for an intermediate energy storage medium, biofuels as a class make a fairly good one, since they are room temperature sotrable and relatively high energy density. But then the question turns to whether they are sufficiently better than anything else to make large scale conversion economically viable.
But I think that when most people here "biofuel" they think of growng stuff and turning it into mechanical energy. In principle, this is fundamentally a means of storing solar energy. The question is one of overall efficiency and opportunity costs. WRT efficiency, can we achieve enough net energy gain over the energy cost of growing, harvesting, processing, and distributing to validate using crops for fuel? WRT opportunity cost, is using crops to produce mechanical energy the best use for cropland?
BTW, I think we should note here that all forms of energy (with the exception of human-produced fusion (if we ever get there)) are ultimately solar in nature. Fossil fuels, crops, wind, hydro all use solar energy at some point in their cycles. Even nuclear fission relies on radioactive elements that were made in a star at some point in the past.
I had to rescue Tony's fusion post from the spam folder - Google's comment spam detector is usually pretty good, but not always. It is 4 comments up from this one.
Fusion might prove viable for space propulsion but not power production. A power reactor not only needs to produce net power, it needs to do so economically.
A fusion drive needs only recover enough electrical power to maintain its cycle - some bleed for onboard services power is desirable but not strictly necessary, and except for a laser star onboard power is insignificant compared to thrust power. And thrust power is (conceptually) simple, just plasma squirting out of the containment, a bug for a power plant but a feature for a drive.
And, at least under my cost model, the energy cost, at current rates, is only a modest fraction of overall operating cost until ship delta v exceeds about 100 km/s, so expensive energy is not a deal breaker if the drive offers other advantages.
But this argument is very generalized - I'll leave it to those who actually know what they are talking about to say how the problems of fusion propulsion really compare to those of fusion power production.
Though obviously one other big factor is mass; I haven't a clue whether a Realistic [TM] fusion installation could approach the magic 1 kW/kg baseline for fast interplanetary travel.
Ignore my count above - just look up a few replies for Tony's fusion post!
Re: Raymond
I'd actually believe fusion propulsion before I'd believe fusion power generation. With propulsion, you're just trying to get a really high exhaust velocity out of the fusion reaction. You don't have to use fusion to completely power the system. You could have a fission reactor for supplemental power.
On biofuels, back when I was reading the tech industry press as a work gig I read a number of pieces on 'second generation' biofuels. Of course most of it is probably vaporware, a press release aimed at venture capitalists. But there does seem to be promise to both algae type techs and techs that can 'burn' a much broader range of plant material - in particular, cellulose.
If either or both of these pan out, biofuels are no longer in competition with food crops - you might be able to just feed the trash, stalks and such, into the hopper.
But the real underlying point is that even under conservative assumptions the fully regenerative techs, though expensive, are no deal breakers for industrial civilization.
The puritanical wing of the environmental movement would likely find the sustainable energy world of 2100 to be acutely disappointing, full of people no more virtuous than today, but getting more utility out of fewer joules.
You pretty much need an onboard auxiliary reactor anyway, for when the main drive is shut down, in parking orbit and during the coast phase of flight. For the inner system you can use solar for onboard power.
But there is an important military footnote here. Nuclear electric drive is extremely well suited to laser stars, because the drive is basically a nuke electric power generator hooked up to plasma thrusters.
All the power is onboard power, which is a horrible design requirement (those huge radiators), but means you've got at least tens of megawatts available to power a laser, pretty much as long as you want to hold the trigger down.
Part of the conceptual beauty of fusion drive is NOT producing all that onboard power, with the resulting onboard waste heat that has to be radiated away. A fusion ship does not need any primary radiators apart from the passive heat shielding of the lantern structure.
But the flip side is that a fusion drive may produce little or no net onboard electric power, so that a fusion propulsion laser star needs an entire separate power plant for its laser installation.
Thus, in a setting where the standard deep space drive is a fusion drive, laser stars are much more expensive to develop and deploy. But a fusion drive will do just fine to sling a kinetic bus.
Not to mention that if you can sling a kinetic bus at 100 km/s it is a true killer bus. I tested a 250 MW laser star, 1000 nanometers near IR through a 10 meter mirror. It just defeats a cloud of 120 target seekers, each about 220 kg, combined total mass 26 tons.
But seeker # 121 saturates the defense, and hits with impact energy comparable to 0.2 kilotons.
So, if your setting has fusion drive as standard, kinetics are relatively favored. A fusion killer bus with release mass of perhaps 100 tons can take out a much larger and more expensive laser star.
Tony, Rick:
The thing with fusion drive is, well, you have to have net gain in order to use it as a drive in the first place (otherwise you still have the same electricity/heat problem as fission). So if you can't already make a fusion powerplant work, you can't make it into a drive worth anything. (Note that it could still be uneconomical as a power source while being a kickass drive bus - I'm talking about ability, not cost.)
Plus, I doubt D-T fusion would make a very good propulsion system, as 80% of the reaction's energy is in the form of neutrons (currently the largest barrier to sustained ignition). This is fine for power generation, but cuts deeply into the advantages of fusion as a propulsion system.
D-3He fusion is merely stupidly hard either way.
If you're doing magnetic confinement, then you need net ELECTRICITY production. In order to get that electricity, you're basically catching neutrons in water to convert it to steam, then run it through a turbine. I want to say that the turbine is only like 40% efficient on the high end. However, in the case of a rocket, you're not trying to convert to electricity, you're trying to convert to mechanical energy. So, all those neutrons dump into your propellant and you're off to the races. My favorite design is Lithium Deuteride/Triteride pellets that detonate with xray lasers. The mixture of deuterium/tritium/lithium 6/7 determine the amount of fusion energy and thus the force of the blast. This works for the smaller drives, but acts like an Orion drive somewhat. Larger drives need more containment to ensure full detonation. For those drives, the fusion fuel is encased in a hohlram to prevent premature fusion (which would blow away most of the fusion fuel without detonating).
In other words, as usual the details are just full of devils.
The neutrons, IIRC, can be used for power generation but only in the same inelegant way as fission plants - heating a boiler for a steam engine.
Raymond:
"The thing with fusion drive is, well, you have to have net gain in order to use it as a drive in the first place (otherwise you still have the same electricity/heat problem as fission)."
You have to have thrust, and you have to have no more power deficit than you can make up with a supplemental power supply. Aside from that, if you have a heat rejection task, well, what power system doesn't?
Rick:
"The neutrons, IIRC, can be used for power generation but only in the same inelegant way as fission plants - heating a boiler for a steam engine."
What is the definition of "elegant" that you're using here? If by "elegant" you mean non-heat engine technology, you have a point. If you mean uncomplicated, well, steam turbine technology is pretty simple.
Citizen Joe:
It's just lithium deuteride - no tritium. The idea of using lithium instead of tritium is that it will be converted to tritium under the neutron bombardment of the rest of the reaction. Usually requires some form of seeding (either small amounts of tritium, or a fission reactor to supply initial neutron flux). And I'm highly, highly skeptical of all the "Orion-lite" drives - absorbing that kind of neutron flux requires heavy metals (usually tungsten) as an ablative shell around the reaction (used as the propellant, really).
If you're just using the fusion reaction to heat hydrogen, without ensuring the reaction products are charged particles (and thus usable with a magnetic nozzle instead of a physical one), then you've just got a nuke-thermal engine. We can do that with fission. That's the real appeal of D-3He fusion as a propulsion system: the reaction products are charged, and thus you can use a magnetic nozzle even if you're using supplementary propellant. That allows you to heat the propellant to millions of degrees instead of a few thousand, and thus get exhaust velocities of many hundreds of km/s.
Tony:
I should clarify a bit, perhaps. Nuke-electric can probably reach 1-2 kW/kg at the very high end, which would require substantial gains in power generation tech (probably magnetohydrodynamic generators - a Japanese team has a version running at 22% efficiency, which is the right ballpark) and radiator tech (NASA has prototypes of a carbon-carbon heatpipe radiator massing about 1 kg/m^2). These designs are all about reducing the mass required to convert the heat into usable electricity; the reactor itself doesn't mass that much. When coupled with a VASIMR-type engine, you can reach exhaust velocities of up to 300 km/s, which is far above the practical maximum given the power level for burn times measured in a few months.
The advantage of fusion reactors would be a much higher specific power (theoretically on the order of 10 kW/kg for D-3He), and even with supplementary propellant to boost the thrust to usable ranges, an exhaust velocity at or above VASIMR's maximum. The limit is more the specific power than the exhaust velocity. At 1 kW/kg an exhaust of 1000 km/s is almost useless - you'll spend so much time burning that you'd get to your destination faster with chemfuel (unless you're talking Neptune or further).
If you have to keep adding energy to your fusion reaction, it's not adding any energy to your propellant that wasn't at some point supplied by your auxiliary powerplant, and then why not cut out the middleman?
And, for the record, I regard fusion engine designs which rely on pulse detonation and ablative thrust shells (Daedalus, HOPE, etc) as thoroughly impractical and probably insanely dangerous to their crew. All of the objections of Orion, just scaled down a tiny bit.
Rick:
Maybe you're just being poetic, but I don't get the constant references to steam engines WRT fission-electric. I have never seen a serious proposal for a spaceborne nuclear reactor which involves steam. Not one. In fact, I've rarely come across one which uses the Rankine cycle at all (and most of those involve sodium or potassium, not water). The common design is a Brayton cycle, usually with helium as the coolant (occasionally supercritical CO2), and is basically a turboshaft using nuclear heating instead of internal combustion. Most of the serious designs only involve phase changes in the radiators.
This is primarily a function of the heat range a space reactor has to operate in to remain efficient (in mass terms). Terrestrial reactors rarely break a thousand Kelvin; space reactor designs are at least a thousand Kelvin on the cold side. Core corrosion is a major, perhaps overriding concern, and there's usually only a single coolant loop, so an inert gas which is only barely susceptible to neutron activation is a major plus.
Also, magnetohydrodynamic turbines are really very elegant. No moving parts, electromagnetic pumps to move the fluids around, everything either solid-state or undergoing phase change to dump heat. No bearings or blades to break or seize. No explosions or rough bursts. Combine with a solid-state engine like VASIMR streaming green or purple flame (argon or hydrogen, respectively) and the overall image is kinda pretty.
That is the nice thing about the He3 fusion. It throws protons, which as charged particles, are easy to convert to electricity (like 90% efficiency).
There's a similar problem with antimatter for power generation. It throws off most of its energy in a form not easily captured.
If I understand the fusion torch concept correctly, most of the heat from the reaction gets dumped into the remass, which means smaller radiators. A fusion reactor however requires ridiculously large radiators.
Re: Raymond
I think you're slightly misunderstanding the point Rick and I are trying to make. Let me try again...
To be useful for propulsion, a fusion reaction doesn't have to generate surplus power or even sustain itself without supplementary power. It just has to generate a high enough exhaust velocity at high enough thrust that it makes sense to use it. The point isn't to make power economically. If the Isp is good, it's all good.
Tony:
Except exhaust velocity times thrust is, um, power.
If it's easier to use an auxiliary fission reactor instead of trying to recover energy directly from the fusion reaction, you still have to be able to create a fusion reaction with a net energy gain, otherwise it's simply parasitic loss.
Raymond:
"Except exhaust velocity times thrust is, um, power.
If it's easier to use an auxiliary fission reactor instead of trying to recover energy directly from the fusion reaction, you still have to be able to create a fusion reaction with a net energy gain, otherwise it's simply parasitic loss."
I think what you are missing is that power isn't measured only at the generator output. If most of the power goes out the back end, well, that's the point. For example, the "power" that makes a chemical rocket work was put in at the chemcial refineries that made the fuel and oxidizer.
Likewise, just because a rocket uses a fusion reaction to generate hot plasma for thrust, that's not fundamentally connected to where the electrical power for containment and compression comes from. The power doesn't all have to come from the fusing isotopes, it can also come from supplementary electrical generation. And the reaction doesn't have to be contained. It just has to be sustained. Google "gas dynamic mirror fusion propulsion" for an example of an engine that could work that way.
I think Rick's reference to "steam engines" is more poetic license than anything else. Any steam engine is an external combustion device, and nuclear electric or NERVA type drives are "external combustion" in the sense they use an outside agency to supply heat energy to the working fluid or remass.
Nuclear fusion drives (especially aneutronic ones) are conceptually far different, since electrical energy and drive power can be taken directly from the fusion products. This takes away lots of the mass problems as well, since we no longer need to convert heat energy into electrical energy or mechanical energy, so conversion machinery, radiators etc. become far smaller and more manageable.
A nuclear fusion drive which needs some sort of auxiliary power supply *might* be feasible if the aux power is very light (or off board and energy is beamed to the ship). Fusion reactions can provide ISP of up to 1,000,000 while NTRs have a theoretical maximum of 1200 and even ORION only gets to 10,000 (but has high thrust as well), so the gain in performance might outweigh the added complexity.
Re: Thucydides
I understand the technological distinction Rick is making. I'm just trying to comprehend why he thinks heat engines are necessarily "inelegant".
Tony:
I think what you're missing is that any fusion powerplant which generates a useful amount of power for heating propellant can also be used for power generation outside of the context of propulsion. If you can generate a hot plasma with more energy than you put in, you can extract (a good chunk of) that energy in some fashion. Charged particles are good that way, whether they're direct fusion products or merely ionized hydrogen.
IOW, if a fusion reactor has a Q value of 0.5 (or anything under 1), then it's not viable for propulsion, either. At a Q value of 10, it may not be economical for power generation, but it still counts as a net power gain for the "will we have fusion power" discussion upthread.
I guess I just can't tell if you don't think we'll get a high enough Q for economical civilian power generation, or we won't break the Q=1 barrier at all.
Thucydides:
Aneutronic fusion is an order of mag harder than neutronic, and Bremsstrahlung losses become significant. D-3He fusion, while hard, still gives more charged particle products than Bremsstrahlung; in Hydrogen-boron fusion, the Bremsstrahlung losses exceed the charged particle output. There's a chance that a strong enough magnetic field can suppress Bremsstrahlung radiation, but that's a) unproven and b) likely going to require magnetic fields a thousand times stronger than we can currently produce.
On Isp:
A high value is only useful if you have the power available to keep the burn times down. A million seconds of Isp does little good if it takes you years to accelerate instead of months.
Re: Brayton cycles
They work rather nicely if all you have to power are your onboard computers and your life support. But they're converters for low amounts of energy. If you want to power an electrical thruster or a laser, brayton cycles are out of the game.
Re: Fusion drives don't need primary radiators
It would be nice, but... you'll need a magnetic nozzle working at 100% efficiency, over the whole spectrum of light. Obviously that's magi-tech. If you have 90% efficiency (I'd say that's *veeeery* optimistic), you still have 10% of some hundred megawats to deal with. Not what I'd call nothing...
Plus, the really annoying thing is that your secondary radiators will oftentimes be bigger than the primaries anyway. That low-temperature heat produced by your electronics is a devil to get rid of...
Still, it would of course be an improvement over a nuclear reactor where you have to get rid of at least 80% of the total output, but you still need radiators.
Jedida:
I think you're thinking of the Stirling cycle. The Brayton cycle is what turboshafts use (I don't think they've got any problem with large amounts of energy). Compress a gas, heat the gas, allow the gas to expand through a turbine, cool the gas, rinse and repeat. This can have an efficiency much closer to Carnot than just about any other thermodynamic cycle we've developed.
You're right about still requiring radiators on fusion drives. Smaller, but still present.
Re: Raymond
We seem to be talking past each other here. All I'm saying is that, in principle, it should be easier to generate a fusion reaction that may require supplementary power to sustain than it is to generate a completely self-sustaining one, especially one that needs to generate a surplus of power in order to be economically justified. Generating, containing, and extracting surplus electricity from a fusion plasma is simply a taller order than generating a plasma and keeping it going with supplemental power. Heck, we can already do that on a very small scale.
So the point is that the requirements of a fusion plasma rocket simply aren't as stiff as the requirements of a fusion power plant. It doesn't have to meet surplus power goals, $ per kw/hr goals, or any commercial goal other than being usefully hot.
Also, please note the term "usefully" above. If a fusion rocket has impractically low thrust, then forget about it. But if it has high enough thrust, in principle it should also have a high enough Isp advantage to be worth consideration.
IOW, a rocketized reaction (chemical or nuclear) generates a lot of propulsive power without having to generate useful amounts of self-sustaining power. Imagine trying to generate electricity by using the gasses coming out of a LH2/LOX rocket nozzle. That's a lot more of a project than just letting the thing fly away. Just so with a fusion rocket -- it doesn't have to meet the sandards of commercial power generation, it just has to be a good rocket.
One interesting thought I've read is to use that obnoxiously hot and fast-moving plasma coming off the drives under thrust as a source for some of your electrical generation. It does sacrifice exhaust velocity, but assuming the math works out, you'd have MHD power when you were under thrust.
As far as the 'inelegance' of a steam plant goes, water is one of the better neutron absorbers. If you're using water as part of your radiation damper (and you can drink the water in a fission plant's primary loop once it cools down to something less than 100 deg C), you can run that hot water through a counter-rotating steam turbine rig with both ends connected to generators, then blow the hot water through a radiator.
While I'd prefer to use something other than water for power generation, your neutron shielding is going to get hot. Might as well take advantage of the fact.
Interesting stuff about fusion.
One small thing, off topic I know but I was curious- does anyone know of any remotely scientific books about anti-matter (or even antimatter porpulsion) with even a shred of credabiity. Its a long shot but I thought I'd ask.
Re: Solar sails.
I googled the term and found few images of any spacecraft beyond the experimental and small scale... and began to wonder what kind of solar system we would have if we had afew hundred/thousand people on such craft making up our "rocket"-punk future.
Trade might be somewhat the same, only v-e-r-y slow and vulnerable to changes in solar weather. More payload than possible with rockets might be carried though.
Warfare might be different- you would have't have a small thruster on board to avoid unguided shrapnel... but no thrust power to even significantly changing one's heading.
Infrastructure: very rare, though perhaps larger than might be put into place with rockets.
Destinations: HEO and possibly Lunar... anywhere else (I doubt so)?
Tony, you seem to have done some work on this sort of thing... I've never even considered solarsail craft as a form of transport- what are your thoughts?
Geoffrey S H:
"Tony, you seem to have done some work on this sort of thing... I've never even considered solarsail craft as a form of transport- what are your thoughts?"
I haven't done any professional work, if that's what you mean. I'm just an interested layman with a little bit of a technical education.
Having said that, what I read suggests that solar sails are not very practical for human spaceflight. Just too slow.
Tony:
I don't think we're talking past each other, I just think your view of the progression of fusion technology is slightly...off. You've got the sequence wrong. Breakeven comes first, and we're close to that. Net power generation comes next. A self-sustaining reaction comes last of all, and at that point it'd be trivial to generate huge amounts of power, but that's the thing which will require the massive breakthrough and may not be possible.
The misunderstanding may come from the nature of Q values and the net power generation phase. Q value refers to the per-reaction/pulse/containment interval. A positive Q means that the reaction gives off more energy than it took to heat and confine the plasma, and the fusion burn was complete enough to satisfy the Lawson criterion. Ignition is infinite Q. We can probably generate power economically at a Q of 20. A Q of 10 might make a decent propulsion system but not quite be economical enough for civilian power generation (which may be what you're referring to). But in general the problem is not considered to be creating a self-sustaining reaction, but extracting enough energy from one reaction to power the next.
It's like a gasoline engine - it requires a spark each time, therefore it's only self-sustaining as a larger system comprising a series of burns, but it's not directly self-sustaining like a rocket engine.
The creation of hot plasma we don't need fusion for - a VASIMR engine uses the same mechanisms for heating plasma as a magnetic-confinement fusion reactor (ohmic heating and ion cyclotron heating), just at a lower scale. The advantage of fusion is that we don't have to supply the energy from another method of generation - the plasma heats itself, if only in pulses.
IOW, if we have to add supplementary power to the fusion reaction during normal operation, it's just a souped-up version of VASIMR, and we're still limited by the other powerplant. And frankly, extracting energy from a plasma is trivial compared to keeping an ignited plasma contained indefinitely.
"Imagine trying to generate electricity by using the gasses coming out of a LH2/LOX rocket nozzle."
The turbopumps extract energy from the gas flow to keep the whole system going - it's not like they're hooked up to a diesel generator or anything.
Scott:
"One interesting thought I've read is to use that obnoxiously hot and fast-moving plasma coming off the drives under thrust as a source for some of your electrical generation. It does sacrifice exhaust velocity, but assuming the math works out, you'd have MHD power when you were under thrust."
That's essentially how fusion drive designs extract the energy required for containment. It's usually just labelled a "direct energy converter" and left at that, but it's either an MHD device (if the plasma flow is continuous) or a magnetic piston (if the fusion reactor operates in pulses).
"While I'd prefer to use something other than water for power generation, your neutron shielding is going to get hot. Might as well take advantage of the fact."
At 100 deg C (373 K) the blackbody radiation is just under a kilowatt per square meter. That's two, almost three orders of magnitude too low to use as an effective radiator in space. That's why we won't be using water for power generation.
As for the shielding getting hot, remember that blackbody radiation increases with the fourth power of the temperature, so letting it run hot make it easier to discard the waste heat. Any attempt to use it for power generation requires you to emit the (still significant) waste heat at a lower temperature, meaning a more massive radiator. This is why 25% efficiency is actually considered about optimal for space nuclear reactors - any more than that and the increase in radiator mass outweighs the power gains.
Geoffrey:
RE antimatter:
Start with looking up antimatter-catalyzed microfusion and microfission, to get an idea of what could be plausible with relatively small numbers of antiprotons. For the larger-scale uses, wait. The recent antihydrogen trap experiment is probably going to end up changing our understanding of antimatter, or at least our understanding of its containment.
For solar sails, check out IKAROS - it's an experimental probe launched by the Japanese space agency on its way to Venus, and it seems to be working well. I agree with Tony about it being too slow for human use, but it might make a hella cheap cargo propulsion tech.
Re: Raymond
With a fusion rocket you don't have to contain the reaction or have it generate enough power to contain and sustain itself. You're just have to get a hotter plasma than external heating methods can create. If you can generate enough power that all you have to do is a dd fusion fuel, that's fine, but it's not necessary.
Tony:
"BTW, I think we should note here that all forms of energy (with the exception of human-produced fusion (if we ever get there)) are ultimately solar in nature."
Fission isn't solar, either.
I also don't think geothermal energy comes from sunlight. Nor does tide-based hydropower.
"Even nuclear fission relies on radioactive elements that were made in a star at some point in the past."
...Well, yeah. Not our sun, though, and in fact elements that heavy are likely to have been made in supernovas, which is (A) far from normal star operation, and (B) only happens to stars too short-lived to harbor life.
Any fusion that isn't pure hydrogen-hydrogen would be derivative of stellar nucleosynthesis as well. There was some primordial helium in the universe, but hardly enough to be much use, so most of what we have comes from stars. The boron in proton-boron fusion is definitely stellar in origin. Not sure about deuterium and tritium, but I'd be suspicious of those too.
Rick:
"And, at least under my cost model, the energy cost, at current rates, is only a modest fraction of overall operating cost until ship delta v exceeds about 100 km/s,"
100 km/s gets you to Mars in 29.6 days, Jupiter in 143 days, and Saturn in 271 days (about 9 months), and Uranus in more than a year and a half. That's ignoring burn times.
Tony:
"You don't have to use fusion to completely power the system. You could have a fission reactor for supplemental power."
This is something I've wondered about sometimes. We already have mixed fission-fusion bombs, but their mechanism relies on the huge momentary pressure of an explosion, so there doesn't seem to be any way to slow the reaction down to make a mixed fission-fusion power plant with better energy output than current fission designs. Would be nice if we did find a way, though.
Rick:
"The puritanical wing of the environmental movement would likely find the sustainable energy world of 2100 to be acutely disappointing, full of people no more virtuous than today, but getting more utility out of fewer joules."
So... how is that bad? I want enough technology to be comfortable, and I want to not wreck the environment.
If technology advances to the point that we can have it both ways at once, awesome!
I've never believed in the ascetic "misery for the sake of misery" ideal. Misery is only a virtue if it's being endured as a cost to something useful.
"The neutrons, IIRC, can be used for power generation but only in the same inelegant way as fission plants - heating a boiler for a steam engine."
Yes. In fact, fission reactions release their energy in neutrons, so it's the exact same process.
If you're willing and able to make steam-boiler-based fission-electric rockets, though, then you should in principle be able to make steam-boiler-based fusion-electric rockets too, if you can get the "fusion" part to work.
For that matter, you could also try neutronic fusion-thermal propulsion, although I dunno what kind of performance to expect from that.
Citizen Joe:
"There's a similar problem with antimatter for power generation. It throws off most of its energy in a form not easily captured."
That's the other problem, besides, of course, "we don't have any antimatter". And that bit about it being hard to keep your ship from exploding. (At least, unlike Orion propulsion, you aren't planning on it being supposed to explode.)
Tony:
"To be useful for propulsion, a fusion reaction doesn't have to generate surplus power or even sustain itself without supplementary power. It just has to generate a high enough exhaust velocity at high enough thrust that it makes sense to use it."
To have both high exhaust velocity and high thrust, you need high power.
Power = 1/2 * exhaust * thrust.
All that power has to come from somewhere.
"I understand the technological distinction Rick is making. I'm just trying to comprehend why he thinks heat engines are necessarily "inelegant"."
They take a bunch of mass and they release most of the energy as waste heat.
"Imagine trying to generate electricity by using the gasses coming out of a LH2/LOX rocket nozzle."
Once it's coming out of the rocket nozzle, it may be a little too late to capture the energy easily. But hydrogen fuel cells aren't exactly magitech.
Geoffrey S H:
"I've never even considered solarsail craft as a form of transport"
It isn't. Solar sails produce single-digit micronewtons per square meter in the inner solar system.
If you have a solar sail the size of 1000 square kilometers - the area of a nice city - that gives single-digit kilonewtons. Put that on a smallish 100 ton ship, and you can manage an actually decent centimeters-per-second-per-second (or kilometers-per-second-per-day) acceleration. You could use this to get to Mars, I guess. Now where did you find a sail that large?
And nevermind trying that trick beyond the asteroid belt.
Solar sails are useful for robotic probes. I wouldn't use them for human travel. (Our current non-sail robotic probes also take years to reach their destination.)
"Destinations: HEO and possibly Lunar... anywhere else (I doubt so)?"
I doubt solar sails are much use inside Earth's orbit. Solar sails have low thrust and gain their advantage from being able to thrust continuously for long periods without expending propellant. The moon is just too close - we can already get there in days with chemical rockets, so why take the slow way building up speed with sails?
(Oops. All four posts above were me.)
I think the fusion confusion is over the rather subtle concept of 'usable power.'
Raymond is correct (I believe) in saying that for a fusion drive to be usable it must do more useful work than you put into it, thus have a positive Q.
But it is not inherently necessary that any of that useful work be in a form you can capture as electric power. A fusion drive might provide its useful work entirely as propulsive thrust, requiring an auxiliary power system for ignition.
A familiar analogy is classical Orion, which provides no onboard power, only a nuclear boot in the butt to hustle you along. In that case the 'auxiliary power' is the HE trigger of each bomb, but the concept is the same.
In practice, if you are using a magnetic nozzle to direct the exhaust plasma and produce thrust, you can almost certainly capture a fraction of output as onboard power, sufficient to maintain the cycle.
So I would be surprised if a practical fusion drive was not self-sustaining, needing only an initial trigger input. But that is still quite a different matter from saying that the unit could be adapted to a practical power plant.
And yes, a fusion drive will require radiators, but arguably only secondary radiators, depending on semi-arbitrary distinctions of terms. (And getting rid of low temperature heat is indeed a pain.)
My comment on nuclear plants as steam engines is poetic license, though in practice most of them drive steam turbines, don't they?
From a strictly engineering perspective there is nothing inelegant about steam turbines - the philosophical dismay is really about using nuclear energy at such low temperatures, and having to pass the energy through an intermediate phase (electrical power) before using it for thrust.
This philosophical dismay does have a practical aspect: mass. Conventional nuke electric drives will struggle to achieve 1 kW/kg. A fusion drive - if we can do it at all - might be able to get 10 kW/kg in thrust power, which cuts travel times about in half.
Solar sails are not terribly practical given the immense size required to move anything beyond a microsatellite. Trying to reef or furl kilometers of sail with feather weight booms or centrifugal force is an invitation to slow motion disaster.
Sails are conceptually far superior to any other type of drive, having an infinite ISP and capable of fairly short flight times due to constant acceleration, and if you can find a practical way to rapidly deploy a sail moving on a parabolic or hyperbolic path around the Sun when you are at the closest approach, you can accelerate to .13 c, so there is reason to study the concept.
IF you are going to build solar sails, then you will need a space infrastructure. A "drydock" in orbit to hold a substrate and a vapour deposition device to lay a layer of aluminum a few molecules thick is the minimum; for the best performance you will also want a means to remove the substrate from the aluminum film and attach the actual spaceship.
That being said, a far more practical means of harnessing the Sun's energy for propulsion is a magnetic or electrostatic sail. The size requirements are more modest, and while the magnetic hoop or electrostatic wands are also fairly whispy constructs, they have greater density and strength than any high performance solar sail.
"I doubt solar sails are much use inside Earth's orbit. Solar sails have low thrust and gain their advantage from being able to thrust continuously for long periods without expending propellant. The moon is just too close - we can already get there in days with chemical rockets, so why take the slow way building up speed with sails?"
No propellant used and thus a better chance of being used again rather than having another built. That's all I can think of. Low proirity shipments on a regular basis to somewhere "near" like the moon. More a small Dhow than a tea-clipper. Nothing that will last for very long if VASIMR works.
Tony:
We don't need hotter plasma without higher specific power. 300 km/s exhaust velocity is unusably high for reasonable transit times at 1 kW/kg, and we can already do that with VASIMR. The lure of fusion as propulsion is the 10 kW/kg range it might be capable of, not the 1000+ km/s exhaust velocity.
Rick:
The low temperatures of terrestrial fission reactors are because of a) the dominance of pressurized-water designs, and b) compatibility with ambient temperature as a heatsink. Space reactors will add a thousand degrees to both ends of the operational range. So no water steam. Maybe potassium steam, but the Rankine cycle is at something of a disadvantage compared to Brayton, so I'm betting on helium coolant and no phase changes.
For radiators, there will still be primaries, even with fusion. D-T fusion is mostly neutronic, so a certain amount of heat will have to be radiated away. D-3He fusion has a significant Bremsstrahlung fraction, so a portion of the x-rays and gamma rays will be absorbed (and thus must be radiated). The primary radiator would still be much smaller than the fission equivalent, though.
Milo:
I don't think solar sails are quite that bad. IKAROS masses just over 300 kg, and with a 200 m^2 sail it can get to Venus in six months. A 300 ton spacecraft would therefore require 200,000 m^2 (under a quarter square kilometer, about 450 m per side) - big, but doable. And when solar sail materials are 3-12 g/m^2, it wouldn't mass very much, either.
Thucydides:
Solar sails are currently constructed of Mylar or similar materials. You wouldn't need nearly so elaborate a construction method as you suggest. They could (and probably would) be constructed in sections, and merely unfurled in orbit.
Geoffrey:
Solar sails would still have advantages for interplanetary cargo, due to their relatively low mass and their lack of propellant (not to mention their near lack of plumbing). Within Earth's gravity, though, I don't see them being very useful. It's tricky enough to pull off some of the maneuvers required for interplanetary travel - doing them in any orbit where the sun changes vector so frequently, and you're asking for headaches.
... not to mention risking the sail ripping apart!
(carbon-nanotube flavour handwavium notwithstanding)
I can imagine this is the sort of thing one would use to improve ISO container freight traffic, slap one on a shipment and you have an inert acceleration device that unfulrs after the container is shot on itsorbit trajectory to its target.
Rick:
"From a strictly engineering perspective there is nothing inelegant about steam turbines - the philosophical dismay is really about using nuclear energy at such low temperatures, and having to pass the energy through an intermediate phase (electrical power) before using it for thrust."
But using nuclear fission as a low temperature heat engine gets years of use out a few hundred kilos of fuel. It sounds perfectly logical and elegant to me. If you want to talk about neutron heating of a liquid or gas by a fusion reaction, that may not be the most direct means of capturing the energy, but it may be the most practical way.
Here's somthing I haven't said before, but it bears thinking about: what if the only way to get a fusion reaction to generate economical amounts of electricity is to have something like a 100 gw reactor that only produces 10 gw of distributable electricity? What if it only costs $0.10 or $0.20 at that scale? Are we going to say it sucks because it's so inefficient? Or are we going to say well, it does put useful amounts of power on the line at a competitive cost? Food for thought...
Raymond:
"We don't need hotter plasma without higher specific power. 300 km/s exhaust velocity is unusably high for reasonable transit times at 1 kW/kg, and we can already do that with VASIMR. The lure of fusion as propulsion is the 10 kW/kg range it might be capable of, not the 1000+ km/s exhaust velocity."
Once again we run afoul of my technological agnosticism. There certainly are things that I don't think are likely, or maybe even possible. But for the things I think are possible, I'm not going to rule them out because they don't fit a preconceived mental model. Here I don't presume that fusion only makes sense at a certain energy level or in a certain form. I just think that if it's useful it will be used, and that a fusion rocket should in principle be easier than a fusion power plant. It doesn't have to meet commercial goals for surplus electrical power production.
Re: Anonymous and solar power
The point I was trying to make is that every bit of energy we can generate or capture is a direct consequence of stellar evolution. We have to think about our energy future in that context -- how do we best use the products of stars?
Tony:
"The point I was trying to make is that every bit of energy we can generate or capture is a direct consequence of stellar evolution. We have to think about our energy future in that context -- how do we best use the products of stars?"
No more so than you need to know botany in order to write a book. Or in order to fell a tree, for that matter.
That nearly everything can ultimately be traced back to stellar processes if you track far enough back is technically true, but it's useless to try to think in those terms when working on practical energy generation technologies.
In any case if you do choose to pay attention to the ultimate origin of energy, then I see a huge difference between (A) using energy that derives from the continuous input of light from our own sun (solar panels, biofuels), (B) using primordial energy that was trapped in the earth during its formation (nuclear, geothermal), and (C) semi-primordial energy that traces back to sunlight after the earth's formation, but relies on the accumulated sunlight of millions of years before humans arrived and cannot keep up with usage in realtime (fossil fuels).
"The puritanical wing of the environmental movement would likely find the sustainable energy world of 2100 to be acutely disappointing, full of people no more virtuous than today, but getting more utility out of fewer joules."
So... how is that bad? I want enough technology to be comfortable, and I want to not wreck the environment.
It isn't bad - just an entertaining irony.
But really I point it out because of the flip side. In some circles 'solar' and 'sustainable' have an irritating eat-your-sprouts overtone. I have no interest in sprouts or moral improvement, only in techs that seem near-future viable and make Earth an efficiently nearly self contained (except for the Sun!) hab for an industrial civilization.
And boy have I got myself in trouble with my remark about nuclear steam engines. Just to put it in context, this is a bias that goes back to my teens - I must have been disappointed on learning that nuclear power was harnessed through something so prosaic and 'old fashioned' (in the 1960s) as steam.
Layered on top of that old prejudice are more practical concerns about weight and plumbing.
All of that said, I typically use the 1 kW/kg benchmark for propulsion estimates here, as a standard that fission electric drives of familiar type can probably attain. In other words, I don't assume or require fusion drives (or other exotic drives) as a baseline.
But keep in mind the limits of a 1 kW/kg drive. It can get you to Mars in about 3 months, but Jupiter is a year and Saturn 18 months. These push the limits of practical human travel, including career radiation exposure unless the hab is very massively shielded.
On the other hand, and rather interesting, a 1 kW/kg drive can make the Earth-Moon trip in about the same time as chemfuel, but with a much lower propellant fraction - important especially so long as propellant has to be lifted from Earth.
Re: Milo
When you're dealing with technology, wht is technically true is important. It amy not make a difference in our day-to-day lives, but understanding where the energy comes from is important in planning how to use it. I think Rick makes a very good point that the word "solar" leaves a bad taste in a lot of mouths. It shouldn't, because stellar level accumulations of mass are what makes it all possible, in one way or another. Even geothermal energy relies on the fact that a nearby star kept the planet from cooling down quite as quickly as it might have, as well as making it possible for water to be liquid on the surface, so that a working fluid is obtainable without using most of the energy of the process to melt it.
The uber thin aluminum solar sail is based on the design developed by K Eric Drexler, and by eliminating the mass of the plastic substrate, is calculated to have a far superior performance to conventional solar sails.
That said, even improving performance by a factor of 10 isn't going to set records between the Earth and Moon, but the continuing acceleration will demonstrate payoffs in longer missions like Earth-Mars or to the outer planets. Probes and cargo can be sent for low cost and a fairly decent "pipeline" without waiting for minimum energy trajectory windows.
As an interesting aside, in theory we could do anything we wanted if we knew how to engineer plants well enough. Jerry Pournelle once suggested (in "A Step Farther Out") that if we could tweak photosynthesis, we would solve the world's food problems (plants only utilize a small fraction of the Sun's energy, between 3 and 6%, so increasing the efficiency would be a huge bonus). Plants also do things like concentrate metals, produce sugars, fats and other substances, and can be tweaked to produce base materials for plastics or drug production (Pharming), so this is solar energy's ultimat expression.
That's part of what I meant by the Biotech Age. The Space Age was really just the opening salvos of the Information Age. The real reason for all the space launches was to get spy sats in the air to get recon on the Soviets. Right now, I think we're getting hypersaturated with information, which leaves us primed for the next great technological age. The move for universal health care is something that will bind us to the pharmaceutical companies. From there, by design or accident, we'll create super bugs (diseases) which will crush those that don't comply. Within a couple generations, we will all be hooked on drugs to combat non-existent ailments and linger through a miserable life prolonged by artificial means. The days of "Life fast, die young, leave a good looking corpse." will have been things of memory.
"At 100 deg C (373 K) the blackbody radiation is just under a kilowatt per square meter. That's two, almost three orders of magnitude too low to use as an effective radiator in space. That's why we won't be using water for power generation."
Who said anything about 100 deg C in the generator loop? All steam plants run a lot hotter than that, it's called super-saturated steam, and uses the pressure-cooker theory. What's the boiling point of water at, say, 300psi? According to http://www.engineeringtoolbox.com/boiling-point-water-d_926.html , it's over 200 deg C. Better, but still not hot enough. At 1000psi, you're talking a boiling point of about 400 deg C.
The problem with using water phase-changes is that they're low-temperature by space terms. Another problem is the mass of structures that can take that much pressure.
"This is something I've wondered about sometimes. We already have mixed fission-fusion bombs, but their mechanism relies on the huge momentary pressure of an explosion, so there doesn't seem to be any way to slow the reaction down to make a mixed fission-fusion power plant with better energy output than current fission designs. Would be nice if we did find a way, though."
Just like an atomic bomb uses conventional explosives to create a critical density (can't call it critical mass), an H-bomb basically uses the atomic bomb to provide the energy for containment (compression to ignition). We're sorta doing the same thing, but there's a couple extra steps in between the nuclear fission plant and the fusion plant.
My bet is that 90-95 percent of the Awesome Stuff / Terrifying Stuff that biotech is supposed to deliver will never happen.
This doesn't mean that biotech won't have an impact, just that it probably won't be any of the obvious, predicted-in-advance ones.
Compare to the cyber revolution. We don't have HAL, we don't have Mycroft, we don't have Colossus. We basically have almost nothing of what Cybernetics was once supposed to achieve.
What we do have is outrageous sheer dumb horsepower, preposterously cheap, and a telephone switching system on steroids. (Which Al Gore actually did more or less invent, from public policy perspective.)
So if biotech is transformative, the transformation will likely be both startling and largely frivolous. You can see the leading edge from here: Botox. On a more substantive level, I would call biofuels for general transportation use not just plausible but likely.
Rick said:"My bet is that 90-95 percent of the Awesome Stuff / Terrifying Stuff that biotech is supposed to deliver will never happen.
This doesn't mean that biotech won't have an impact, just that it probably won't be any of the obvious, predicted-in-advance ones."
I tend to use Sturgon's Law: 90% of anything is crap; that applies to innovation most of all. The only thing we can be sure of is that we won't know which 10% will pan out until it is right on top of us.
My point is that the search, not the finding (only the possibility), is what is important to us. The search is McGuffinite, not some specific thing.
Ferrell
Yes ... Sturgeon's Law has a great deal to recommend it. Most innovations are vaporware; the few that aren't make all the difference.
Note, by the way, that much of what I said about the cyber revolution could be said about the space age - it has had enormous impact, even though most of it has not been the Cool Stuff we anticipated.
Thucydides:
"Jerry Pournelle once suggested (in "A Step Farther Out") that if we could tweak photosynthesis, we would solve the world's food problems (plants only utilize a small fraction of the Sun's energy, between 3 and 6%, so increasing the efficiency would be a huge bonus)."
One wonders just how much one can improve this without radically redesigning their biochemistry to be something that is not so much a "plant" as a "food vat with solar panels". Having access to an order of magnitude more energy would seem to be useful enough to normal plants in the wild that if it's plausible, you'd wonder why none of them have evolved the capability yet naturally.
Why plants haven't evolved a higher level of efficiency is probably a case of nature's settling on "good enough". For all practical purposes in the wild, 3-6% probably is sufficient.
If we really want or need to change the world, radical modification of plant metabolism will probably be the means (elbowing fusion and space aside in the process), with unintended and totally unexpected consequences (both positive and negative). Once the gene for hyper efficient photosynthesis gets "in the wild", mowing the lawn will become sheer hell.
This could be worked into a story/game/virtual reality scenario in two different forms; out of control "triffid" biotech strangling the biosphere and forcing an exit from Earth. The other entry is the development of high efficiency biotech to support self contained biospheres off Earth.
Re: sunshades to control global warming
That does nothing for the other problem with adding CO2 to the atmosphere, ie: changing the chemistry of oceans so it's harder for sea life to make shells. Far better to build non-fossil energy sources, mostly nuclear.
Rick: about your 'disappointment' at getting electricty from nuclear using 'old fashioned' steam. Some alternate fission reactor designs such as the Molten Salt Reactor have higher operating temperatures so closed cycle gas turbines (Brayton cycle) become the preferred method of turning nuclear heat into electricity.
Raymond: "It's tricky enough to pull off some of the maneuvers required for interplanetary travel - doing them in any orbit where the sun changes vector so frequently, and you're asking for headaches."
I've played with a solar sail simulator I wrote & while there are headaches they are greatly reduced by making the solar sail equally reflective on both sides. Say you start your sail in an orbit in the ecliptic plane a bit above the worst of the space junk & want it to spiral out to start an interplanetary trip. You keep turning your sail so as maximize the thrust component in the direction you are currently moving. If your sail is reflective on only one side you need a quick 180 degree rotation as you pass the point on each orbit that you move directly toward the sun, but if your sail is reflective on both sides you just have the sail rotate a full 360 degrees for every 2 orbits about the earth & it passes through the edge on orientation as it is going toward the sun. Some headaches still arise because keeping the optimum orientation requires the rotation to speed up & slow down, but at least no outrageously quick flips are needed.
Some of the issues with solar sails, namely handling them, may or may not be major problems - we won't know until we try it. (The same goes for the enormous wings needed for solar electric drive.) Though I suppose the more formal engineering problems can be simmed.
One other limitation to solar sails is, in effect, the lack of a keel. A solar sail can fall sunward by setting it to counteract orbital motion, but it can't accelerate sunward, only fall. I think this limits its speed on inward trips, e.g. Mars-Earth, relative to electric drive.
For slow cargo that doesn't much matter, but I imagine that most slow cargo will be heavy, requiring really large sail areas.
Rick:
"We basically have almost nothing of what Cybernetics was once supposed to achieve."
With the exception of true AI and humanoid robots, we have so much more than was ever predicted. yes, it's very brute force in some ways, but that doesn't diminish the capabilities we now have to store, analyze, and communicate data, way beyond anything that was expected.
Rick:
"One other limitation to solar sails is, in effect, the lack of a keel. A solar sail can fall sunward by setting it to counteract orbital motion, but it can't accelerate sunward, only fall. I think this limits its speed on inward trips, e.g. Mars-Earth, relative to electric drive."
Solar sails are always going to be limited by their low thrust to slowly modifying their orbits in or out from the Sun. Comparing them to relatively high delta-v nuclear/solar-electric rockets is just abit apples and oranges.
Rick:
"I think this limits its speed on inward trips, e.g. Mars-Earth, relative to electric drive."
Some quick calculations: to fall from Mars's orbit to Earth's orbit, assuming you can completely cancel out your velocity, would take 85 days. Falling all the way to Sol would take four months. Falling from Jupiter to Mars would take over seven hundred days.
These are theoretical optimums assuming you can instantly move from planetary orbit to solar freefall and back, which of course you won't with a solar sail's low thrust. Real trip times will be longer, probably much longer. However by that token if the outbound trip already takes a really long time, I'm not sure how much extra difficulty you get on the inbound trip. I think the acceleration from freefall gravity actually compares favorably to the acceleration from solar sail thrust.
See: http://en.wikipedia.org/wiki/Free_fall#Inverse-square_law_gravitational_field.
Tony:
"With the exception of true AI and humanoid robots,"
And we already have humanoid robots. It's just that without true AI, they're not good for much except research prototypes and sex dolls.
Milo:
"And we already have humanoid robots..."
In the future, can we assume that I know about technological stunts like Asimo, and therefore that I'm talking about the substance of real issues?
Jim Baerg:
"Rick: about your 'disappointment' at getting electricty from nuclear using 'old fashioned' steam. Some alternate fission reactor designs such as the Molten Salt Reactor have higher operating temperatures so closed cycle gas turbines (Brayton cycle) become the preferred method of turning nuclear heat into electricity."
That's still the heat engine approach, which I think is what Rick is objecting to.
Also, running a reactor at higher heat should, in principle, use up the fuel faster. Maybe it uses the fuel more efficiently, but I'm not sure.
Having thought about it a little more, I'm not sure there's a way to extract electrical energy from a controlled nuclear reaction except through a heat engine. Neutrons and electrons are extremely weakly interacting at best. So neutrons passing through any conceivable material just aren't going to cause electrons to be tossed off to be absorbed by conductors. If they could, they would certainly do it in the water of a fission power reactor, wouldn't they?
“Or, you know, we could just stop making all those greenhouse gasses.”
Space-based climate-control infrastructure is almost certainly less expensive in the plausible near future … and about as equally unlikely to happen, at least through governmental efforts. It’s a McGuffin for fiction after all.
As for the grand space future, I wouldn’t count on it just yet. I think human civilization has even odds of collapsing again before we get that far.
Re: molten salt reactors in space applications
The problem with molten salt cooling is that the coolant is solid at STP. This would lead to all sorts of complications during low power operation and require auxiliary machinery -- and extra power -- to manage offline coolant reservoirs.
M. D. Van Norman:
"As for the grand space future, I wouldn’t count on it just yet. I think human civilization has even odds of collapsing again before we get that far."
I wouldn't go anywhere near that far. But the perceived economic imperatives for a human space future just aren't all that compelling. Our future in space, to the degree that it exists, is most likely going to be based on exploration and expansion. It's therefore likely to be driven by scientific curiosity and national/cultural pride. And with the price tag that comes attached, those motives are going to take quite a long while to play out.
Don't forget that all those experiments on the ISS will soon be done with robots, so even that won't be needed.
I can see the number of humans in space going down to nothing within the next 20 years- and staying that way.
If you can write a space opera with yhumans on earth reacting to the actions of robots in space... then your're fine.
Tony:
"Having thought about it a little more, I'm not sure there's a way to extract electrical energy from a controlled nuclear reaction except through a heat engine."
That would be a fission-fragment reactor. It's a highly speculative idea at this stage, but it works on the same concept that aneutronic fusion reactors are supposed to derive their electricity from.
M. D. Van Norman:
"As for the grand space future, I wouldn’t count on it just yet. I think human civilization has even odds of collapsing again before we get that far."
Again? When was the last time?
The falls of various empires have caused minor setbacks in technological progress, but none ever returned us to stone age level sophistication, let alone worldwide. A major collapse of civilization would delay our rocketpunk future by maybe a few centuries, but would hardly deter it.
Re: Geoffrey S H
Our robot explorers do nothing but collect raw data. While that data is useful in building a picture of our greater cosmic environment, it's still just data. Nothing can replace actually sending people there.
This is one of those purpose of life things, like art, music, and science itself. The purpose of learning is ultimately doind, or at least appreciating, in person. That will drive people to go and institutions to send them. It just won't be a lot of people at first.
They are working on solar molten salt reactors nowadays as well. The idea is that when the molten salts reach a critical threshold, it gets replaced with a purge fluid. We've been doing that sort of thing for a long time in cold climates when you winterize your engines.
Now if you can justify keeping your reactor warm during non peak hours, you could almost do away with the purge cycle. The big question is the comparison of max power/standard power/minimum power generation. I'm guessing that standard power will be pretty close to max power production due to mass requirements and production costs. So if your reactor is rated at 200 kW (enough to run a couple VASIMR), max power might be something like 220 kW, and warm minimum would be like 20 kW, about 20 times the usage of a typical home. What do you do with that idle power?
“Our future in space, to the degree that it exists, is most likely going to be based on exploration and expansion.… And with the price tag that comes attached, those motives are going to take quite a long while to play out.”
Long enough that the Accelerando can turn into the Big Slowdown. Is that not a possible consequence of the climatic catastrophe I was alluding to?
“Again? When was the last time?
… A major collapse of civilization would delay our rocketpunk future by maybe a few centuries, but would hardly deter it.”
The fall of Rome has been cited as creating a delay of several hundred years, and delays are all we’re talking about in this case. However, I also find it plausible that at least one previous civilization was destroyed by the last climatic revolution.
M. D. Van Norman:
"Long enough that the Accelerando can turn into the Big Slowdown. Is that not a possible consequence of the climatic catastrophe I was alluding to?"
In reverse order:
Since I don't believe in climate catastrophes, please go peddle it to someone else.
I also don't believe in technological singularities or even significantly faster technological progress than we've been experiencing for about the past 500 years. Also, I think that just about everything that Stross writes is a total shuck, designed to take in people without a serious technical or scientific education, but possessed of the (all to commom) predisposition to unquestioningly accept ridiculous social, cultural, and historical stereoptypes. It's basically Baen-level tripe, just in the opposite political direction
“Since I don’t believe in climate catastrophes, please go peddle it to someone else.”
I’m not peddling it. With so much politics involved, I think the “science” is suspect. Again, though, it is a McGuffin (in more ways than one, in fact).
I had to look Stross up, so I have no idea what his definitions are. I was using “accelerando” to mean rapid technological progress. I first saw the term in Robinson’s Mars trilogy, but it seems apt for our era.
Re: M. D. Van Norman
I would have thought that "accelerando" would have been acquired from Stross, given its use in context. But he did crib it from Robinson.
In any case, technological singularity is both scientifically and ethically suspect in my opinion. Scientifically, I think all of the evidence we have is that any process is much more logistic than quadratic in nature. IOW, everything has its limits. Ethically, it strikes me as a wish fulfillment fantasy for people who want to escape humanity -- their own humanity in particular.
WRT climate issues, my sincerest apologies for coming down so heavy, but in my experience climate talk derails many more discussions than it informs.
So far as 'progress' goes the fall of Rome is quite ambiguous. Technologies that involved big price tags, like monumental architecture, were set back. But technologies like the moldboard plow and powered mills spread.
More remarkably, and something people have only recently noticed, at the level of high culture there was progress as well. Britain as a Roman province produced no native written record beyond brief incriptions. In the next 300 years, the traditional Dark Ages, it produced a body of literature the fantasy shelves are still recycling, and Bede, who is still in the philosophy corpus.
The whole idea of collapse can be ambiguous - see Economic Bubbles in SPAAACE !!!
On climate catastrophe, I think it is certainly possible, a long ways from saying inevitable or even likely. By lucky coincidence, unless there's a subtle underlying shared cause, we became aware of global warming just as the cheap oil era is ending.
We have pumped the low hanging fruit, and industrialization is going global. Even if there were no alternative techs and no other considerations, we'd be talking about expensive recovery from oil shales, coal gasifications, all that stuff.
God knows we could easily screw up, but I'm sanguine about at least the possibilities of this century.
A meta comment on global warming. I'm amazed that it is in any way controversial in a crowd like this, because the whole question is at bottom a matter of planetary science. No one would have a friggin clue if we hadn't gone to Venus, Mars, et al.
But one consequence is that climate scientists are now treated like medical doctors, and human nature being what it is they have learned to act like doctors. I take what they say in that light: conceptually valid, but no hazard will ever be understated.
I think the accelerando, in human terms, was about a century ago, say 1880-1930.
At the beginning of that period, people nearly everywhere lived in an essentially postmedieval technology. Most people worked the land, largely with hand tools, though steam farm machinery was starting to appear.
Railroads and steamships were available for long distance travel, but local travel was still almost entirely by foot, horses for the well to do. Lighting was by candle or oil lamp, in a few places gaslight. The telegraph provided instant comms, but only between relatively few stations and with extremely low bandwidth. (How many baud could a telegraph operator achieve?)
By 1930, millions of people were living broadly the way people live today. They drove cars home to houses with electric lighting, where they could stay in touch with friends by telephone, and stream entertainment by radio or play it from recorded media on the phonograph.
To a person before 1880 the domestic technology of 1930 and 2010 is hardly distinguishable, except that now we carry the telephone and Victrola around with us. Likewise a 747 is no more awesome than a DC-3 to someone who never thought people could fly.
I see that era as a quantum transition. In military terms WW I pretty much made the whole transition; people went in with cavalry and came out with planes and tanks.
Rick:
"A meta comment on global warming. I'm amazed that it is in any way controversial in a crowd like this, because the whole question is at bottom a matter of planetary science. No one would have a friggin clue if we hadn't gone to Venus, Mars, et al."
I think we would have noticed climate change without planetary science. What planetary science has done is give people seemingly easy answers to remarkably complex questions.
"I think the accelerando, in human terms, was about a century ago, say 1880-1930."
I think that is insightful. We have to be careful about the difference between knowledge and experience, however. My father, who was born in 1937, could tell you about heating water for the bath on a stove. My mother, born in the same year, could tell you about Southern Missouri before rural electrification.
If we insist on using the term "accelerando", then I think it is still in effect WRT the rapidity with which innovations penetrate the society at large. New conveniences generally don't take years or even decades to reach most people, like electricity or hot running water did. They're available at your local Wal-mart on the scheduled day of release. Or maybe that's not accelerando as much as it is the new normal, to borrow an expression.
"In military terms WW I pretty much made the whole transition; people went in with cavalry and came out with planes and tanks"
Murray and Millette made this point in their operational history of WWII, A War to be Won. They pointed out that a lieutenant in 1914 had little in common with the colonel that he himself had become by 1918. Yet that same colonel would have easily recognized the overall form, if not the detail, of war in the 1990s.
I think the rapid penetration of innovations is indeed the new normal. And many innovations a century ago were adopted with startling, 'modern' rapidity.
A practical electric railway technology was introduced by Frank Sprague in 1888; by 1910 every city and larger town had electric streetcars, mainline electrification was starting - and electric railways were already starting to be threatened by the automobile.
The time scale is pretty comparable to the rise of the wired Internet, and now the wireless challenge. By comparison, the more gradual spread of rural electrification was a bigger process, nearly the spread of industrial civilization itself.
While the Roman Imperium collapsed and took down the bureaucratic infrastructure that made building build roads and aqueducts possible, lots of low level innovation continued to happen.
By the early middle ages, animals could be kept alive over winter by feeding them hay. People could wear warm clothes due to the invention of knitting; both innovations unknown to the Romans. Other things like windmills filtered in from other civilizations and spread through Europe, so maybe the change from a centralized, heavily taxed and regulated society to a far more decentralized form allowed low level innovation to grow and spread.
Climate has changed over the course of history, European culture and technology grew and spread during the Medieval warm period, while the stresses of the Little Ice Age also triggered lots of social unrest as crop failure became more common. (An interesting historical footnote; the American Revolution occurred about the tail end of the Little Ice Age, many of the frozen rivers that Washington could cross in the 1700's were ice free by the time of the American Civil War).
M. D. Van Norman may have been referring to the theory that the late Bronze Age civilizations collapsed due to something similar to the little ice age causing widespread famine, unrest and mass migration, but evidence for that is pretty sketchy at best.
An interesting question would be whether plausible future advances will count as another accelerando or simply as more incremental changes stemming from the last one. If orbital access or even interplanetary travel becomes even semi-routine, is this as big a change as the development of powered flight or is it just a logical extension of the latter? Would phones, radios and computers becoming compact and cheap enough to be integrated into clothing be simply another step along from the development of mobile phones and personal stereos, or as revolutionary as the work of Marconi and Bell?
It also occurs to me that there are still people in the world today who, from poverty or religious conviction, live a lifestyle that is in many ways pre-accelerando. The advent of another accelerando, whatever form it might take, could leave people behind in a similar way, whether by their own choice or not.
R.C.
Interesting question about what constitutes an accelerando.
Most of what I talk about on this blog is clearly not an accelerando. Interplanetary travel? We already have that tech, in outline - the only reason we haven't gone to Mars is that no one has written that $200 billion check to develop and build the actual hardware.
Re: Rick
I think accelerando can only be identified in retrospect, much like Rick did WRT the late-19th/early-20th Centuries. It's just one of those things that close proximity distorts.
R.C.:
"The advent of another accelerando, whatever form it might take, could leave people behind in a similar way, whether by their own choice or not."
Cybertech would most definitely leave a lot of people who don't want to be "upgraded". Particularly if it involves stuff like neural interfaces.
Milo:
"Cybertech would most definitely leave a lot of people who don't want to be "upgraded". Particularly if it involves stuff like neural interfaces."
Implanted computer interfaces strike me as the cyber version of plastic fantastic titties. The people who are cool -- or who want to be cool -- will get them, but it won't really impact people who just want to get business done.
Neural implants like that are going to make people stupider in the long run. They'll use the system to reference the internet rather than actually memorizing things.
Implanted computer interfaces strike me as the cyber version of plastic fantastic titties. The people who are cool -- or who want to be cool -- will get them, but it won't really impact people who just want to get business done.
I'm not so sure. The whole technology strikes me as less plausible in general, but we have barely tapped neurology so far. Once the brain is better known, it might get possible, or it might not.
IF it comes around, I could imagine that it changes day to day matters by quite a bit. Nothing absolutely radical, but at least enough to leave anyone not participating at a serious disadvantage. I can't even start to count all the seconds I'd save every day if I had even as primitive a thing as a standard TI-calculator plugged into my brain to do the number crunching for me, and I'm someone that does not use it *that* much.
More severe would be the possibility of actual data storage connected directly to the brain. Imagine having Wikipedia on callup without actually having to read it. People without such implants would be at a very severe disadvantage economically. We probably wouldn't recognise our schools anymore.
Neural implants like that are going to make people stupider in the long run. They'll use the system to reference the internet rather than actually memorizing things.
That has nothing to do with stupidity. My generation was already memorizing a lot less at school than people used to 50 years ago, and I wouldn't call us more stupid than the last generation for that.
The focus shifted heavily to analytic thinking and thought processing, because that's the requirements of our time: You can get the information, so knowing the information is secondary. You have to be able to make use of it, that's what counts.
I was free to look up my formulae at every test in professional school, while my father who learned the same job 40 years before me had to memorize them all. I'm not more stupid because of that, because the chances of finding yourself without a reference are almost nil nowadays, so it doesn't make much sense to memorize them in the first place. If the access to information becomes even more easy, that trend is likely to continue.
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