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Fusion Rocket Could Take Us To Mars
New submitter imikem writes "University of Washington researchers and scientists at a Redmond-based space-propulsion company are building components of a fusion-powered rocket aimed to clear many of the hurdles that block deep space travel, including long times in transit, exorbitant costs and health risks. 'Using existing rocket fuels, it's nearly impossible for humans to explore much beyond Earth,' said lead researcher John Slough, a UW research associate professor of aeronautics and astronautics. 'We are hoping to give us a much more powerful source of energy in space that could eventually lead to making interplanetary travel commonplace.' 'The research team has developed a type of plasma that is encased in its own magnetic field. Nuclear fusion occurs when this plasma is compressed to high pressure with a magnetic field. The team has successfully tested this technique in the lab. Only a small amount of fusion is needed to power a rocket – a small grain of sand of this material has the same energy content as 1 gallon of rocket fuel.'"
Marty, where we're going, we don't need roads......
erm... if they've got nuclear fusion working, couldn't they just forget about Mars and work on making it available as a power source to replace conventional powerplants to solve the world's energy needs?
...Polywell?!
Will it be added to Kerbal Space Program?
Can't wait to have a generator and fusion reactor!
Just do not let anyone with the demeanour of Brian Blessed captain the mission.
First. Penis
Well, you are a dick, so there's that.
How is the electricity produced in the space ship for the nuclear fusion, would it also be nuclear? "The capacitors are hooked up to a giant magnet that houses the chamber where the fusion reaction will take place. With the flip of a switch, the capacitors are simultaneously triggered to deliver 1 million amps of electricity for a fraction of a second to the magnet, which quickly compresses the metal ring."
Some people die at 25 and aren't buried until 75. -Benjamin Franklin
I don't think practical fusion technologies are as far away as you're acting like they are. If you've been following fusion news, there are several projects that are getting pretty close to scientific net+(my favorite is the Focus Fusion experiment).
There are a few small details to deal with regarding both potential technologies.
Except we know how to create uncontrolled fusion, and a fusion rocket is closer to a hydrogen bomb than a fusion reactor. You're just trying to make fusion happen and throw the resulting plasma out the back, not keep the plasma in one place and generate power from it.
Wait, you are talking about Gillett, aren't you?
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
But apparently there can be good things from Redmond, like nuclear fusion-powered spaceships :-).
So basically what you're saying is, "What could possibly go wrong?"
As Silicon Dioxide (silica, a component of sand) is not noted for its fusing properties, I was guessing that the fusion would be from more typical materials: hydrogen, or perhaps helium.
And while liquid hydrogen technology is well developed, liquid helium is a bit more difficult, and metallic hydrogen even more so. A "grain" of (metallic) hydrogen seems a bit beyond expectation. A grain-sized amount of hydrogen, I'd believe. But a tank of granulated metallic hydrogen?
The Trisops machine at the University of Miami.
Disclosure: I am one of the authors of the cited paper in the article and the author of the above Wikipedia article
What's not clear in the article is how they plan to power the drive... I seriously doubt solar will be sufficient (mostly due to the low insolation at Mars), which means nuclear. Which means *heavy*.
What about radiation shielding?
Lets not forget that the objective of the rocket is to move you, not generate usable energy. You don't necessarily have to have a net+ for this to be useful.
Think of it as a super high density fuel that just takes a lot of energy on the ground to process.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
boom.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
Man... Fusion Drives, Plasma Drives, Ion Drives... now I really want to play Master of Orion 2.
Might sound wacky but Bob Lazar somewhat discusses the traveling technology behind the crafts he worked on and it sounds just about 2 levels above this.
âoeUsing existing rocket fuels, itâ(TM)s nearly impossible for humans to explore much beyond Earth,â said lead researcher John Slough, a UW research associate professor of aeronautics and astronautics. âoeWe are hoping to give us a much more powerful source of energy in space that could eventually lead to making interplanetary travel commonplace.â
[...]
NASA estimates a round-trip human expedition to Mars would take more than four years using current technology. The sheer amount of chemical rocket fuel needed in space would be extremely expensive â" the launch costs alone would be more than $12 billion.
That's not true at all. Chemical rockets work as well. And with the Falcon Heavy in the near future, there's no reason to pay $12 billion in launch costs for a Mars mission, even if you use chemical rockets.
Note also the phrase "take more than four years". That makes it sound like it takes two years to come and go from Mars. It really only takes six months with chemical rockets (plus some time for attaining Mars orbit, there's probably not going to be a direct landing on Mars due to the high risks of aerocapture) The reason it would take that long is because humans would be staying on the surface of Mars for at least two years. I doubt even instantaneous travel would cut off more than a year and a half.
The more reasonable 90 day passage to Mars would takes six months off the travel time plus reduce the time needed to get into Mars orbit. It would also enable trips at any time rather than just during the most optimal trajectories. This really is the key constraint of chemical rockets.
At this point, it is worth noting that there are other viable near future propulsion technologies as well. A key one is electric propulsion which can be solar or nuclear powered. It has a good mass fraction and travel times. Solar sails could be used to ferry radiation-immune loads over very slowly.
First.. fusion reactors, next, manufacturing spaceships in space (cool designs, no need for rocket fuel, as big or as small as you want), third.. terraforming, fourth.. galactic travel
Anyone want to make a guess on how long it'll be? 50 years? 100 years? 150?
The Ford Focus Fusion is designed to move you.
Whoosh!
Learning HOW to think is more important than learning WHAT to think.
In space no one can hear you boom.
That's no problem. They use platics for that.
-- Betting on the survival of the media industry is a serious risk. I advise investing elsewhere.
Pff radiation shielding is overrated.
And think of all the tasty settlers we could eat after a nice radiation bath.
Mod me down, my New Earth Global Warmingist friends!
You're thinking of fission. You don't need all that much shielding for fusion, that's the beauty of it!
What about radiation shielding?
If you're using a nuclear rocket, you have plenty enough payload to add any required shielding. Besides, you want as many fusion products as possible to go out the back of the rocket, not the front.
"could" take us to Mars as well.
Unfortunately, harnessing fart power has proven much more elusive than fusion power.
You can also make a really long space ship, with the engine at the far end. Most radiation will then miss the front end.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
So, this thing will go WHUMP! once a minute? It will be the most annoying and uncomfortable journey ever and forget of sleeping.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
These guys are claiming to have controlled thermonuclear fusion above breakeven. That's huge. No one has ever done that. If it works, we have a new major power source. They write: "Now, the key will be combining each isolated test into a final experiment that produces fusion using this technology". That's a Nobel prize if they succeed.
This is too important to let NASA fuck up.
You're going to need radiation shielding anyway due to the uncontrolled nuclear reactor that sits at the center of the Solar System.
Seems like an appropriate name for a very fast nuclear powered vehicle where we don't have to worry about disposing of the exhaust left in its wake right?
--- Mercutio was right.
I don't we can ensure that Redmond is destroyed if they launch from Bellingham.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Only a small amount of fusion is needed to power a rocket – a small grain of sand of this material has the same energy content as 1 gallon of rocket fuel.
Fusion is a process, not a material.
The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
It was the NERVA rocket. it wasn't fusion, but it was a nuclear-powered rocket, and it would have easily made Mars our bitch.
It was canceled to, fucking get this, no seriously, wait for it. It was canceled TO SAVE THE BUDGET because the politicos at the time were afraid a successful Mars rocket would "drag" the US into this huge "space program" where we'd explore the solar system and stuff. And that would cost a lot of money.
Instead, we killed the NERVA rocket and saved our budget for Vietnam, which was a roaring success that paid incredible dividends . . . . oh, fuck.
Anyway, this is nice to hear, but I'm not going to hold my fucking breath. Our national priorities are far too ass-backwards for something forward-looking like a Mars mission. I suspect the first people to land on Mars will likely be an international team, and America will be riding along in the back begging for a look out the front window from time to time.
One day I feel I'm ahead of the wheel / the next it's rolling over me / I can get back on / I can get back on
Might as well use fission based energy then.
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As in Bullshit
I'm an American. I love this country and the freedoms that we used to have.
Actually that is fairly well controlled. Its excursions (flares, CMEs) are tiny compared to its steady-state output.
Problem is we don't know how to make a controlled reactor that isn't significantly bigger than the entire planet and uses gravity for confinment yet.
retrorocket.o not found, launch anyway?
You need plenty of neutron shielding for fusion. But the advantage of having a spacecraft over a power plant is that you can use distance, by putting it on the end of a long structure, and that you won't care what the neutrons will do to the shielding and equipment on timescales longer than the mission.
I hear we're about 40 years away from viable fusion technology.
All technologies that can be discovered have been discovered. How many laws of the universe does this perpetum mobile violate?
We are talking about fusion here so of course it perpetually will be available in 20 years.
Average Intelligence is a Scary Thing
Shouldn't that read "Fusion Rocket Could Blow Us To Mars". No, I did not RTFA. Who has time for that.
I dunno, the Z machine at Sandia looks pretty nice.
Classical fusion (not he-3/deuterium) emits extremely high energy neutrinos that tear up shielding. This I'd one of the major hurdles in *reactors.*
So suppose this works as described and we have a functional method of initiating pulses of controlled fusion in a rocket engine that when vented out the nozzle produces usable thrust. Let's make that nozzle thinner and a bit more tubular than conical - a few hefty magnets around to to keep all that fusing stuff in a nice thin stream. While we're at it lets anchor the other end of the rocket to something HUGE that the thrust isn't going to have a prayer of shifting. Except here we call it recoil, because if you have made a fusion rocket you have also created the other staple of grand space opera... A plasma cannon :)
I had a
This is just a process for converting electrical power into propulsion with a decent specific impulse. If you wanted, you could generate the electricity with fission, or any other convenient way. However, this method should have better specific impulse than a more direct fission based drive (e.g. using the fission to heat the fuel), while being more efficient than other electricity based methods of a similar specific impulse.
Clearly a Ford man.
Well, sure you do! If you don't have a net+, you're just wasting energy. You take energy X and convert it to YX, which is then used for propulsion. That makes no sense. For that grain of salt to be used, you'd have to carry around 2 gallons of fuel.
Neutrinos? That doesn't sound right. Did you mean "neutrons" (and I honestly don't know)?
And how not to kill all involved? No mention of that in the article from my quick read.
Ok, apologies if this is a joke that's wooshing over my head, but nuclear fusion produces very little radiation. A small fraction of the reaction energy is released in neutrons and some x-rays. Most of the energy is released as heat. I'm not a nuclear physicist, but hydrogen fusion is causing hydrogen atoms to smack into each other with enough energy that they fuse producing helium and a very large amount of energy. You're thinking perhaps of fission, which is when radioactive isotopes give off energy as they change into different radioactive isotopes. It's a completely different thing.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Unless your form of energy X is not useful for propulsion or every other method of using it for propulsion is less efficient for a desired specific impulse.
The devices we call 'hydrogen bombs' are not pure fusion explosives. They are more correctly known as 'hydrogen-boosted fission' devices. The hydrogen fusion is used to provide more neutrons to sustain the fission reaction, but in most cases the majority of the energy still comes from fission.
(At least, that's my understanding.)
The obvious solution is to go so fast the radiation never catches up. I hear that electromagnetic energy has some sort of hard speed limit, perhaps they could just go a little faster than that?
Pretty sure you're right in that he meant neutrons. Neutrinos will pass through almost anything, so no worry about them "tearing up" anything.
Reality: Wont.
The basic engineering and physics have been known from more than 60 years. Still, the question comes to cost and return. The cost is still 'astronomical' the return near zero.
Many of the possibilities realized during the 1800s industrial revolution are still hopelessly out of reach for financial reasons.
If my granny had four wheels she would be a bus and could drive me to work!
The devices we call 'hydrogen bombs' are not pure fusion explosives. They are more correctly known as 'hydrogen-boosted fission' devices. The hydrogen fusion is used to provide more neutrons to sustain the fission reaction, but in most cases the majority of the energy still comes from fission.
(At least, that's my understanding.)
Correct. Fission --> Fusion --> Lots More Fission --> Very Big Kaboom
Although the energy density of hydrogen fusion is greater than that of Uranium/Plutonium fission, the energy of individual fusion reactions are generally much less energetic than individual fission ones. H-bombs are crazy because fusion produces high-energy neutrons (and lots of 'em), which are sufficient to cause fission in normally non-fissile U238. So, they jacket the fusion part with cheap U238, which is useful as a tamper for slow neutrons until the fusion fuel ignites (by way of energy from a separate, fission primary), after which the cheap U238 is fuel for boosting the yield off the charts.
Take it easy, Charlie, I've got an Angle...
'S'plain to me again how igniting nuclear fusion under my ass reduces my health risks? I must have blinked.
Question, does your car require you to carry around raw, unprocessed oil, complete with an oil refinery to convert it into gasoline, or can you just fill it straight with gasoline?
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-
All of the fusion projects that I'm aware of are not only heavy, they're also delicate, and require lots of skilled technical attention.
I'd say we're *at least* two decades from a fusion engine that's practical in a spaceship. Three or four wouldn't surprise me. And I also wouldn't be totally surprised if it is one of those things that can just never be made practical (though I'd be very disappoiinted).
For that matter, while several of the fusion projects appear to be near the technical "break even" point, I can't think of one of them that's even approaching the economic break even point. Even fission is a bit dubious about that, when you count in all if the expenses. (E.g., government providing "insurance" against massive problems [in the form of saying "you won't be held liable"], and what to do with spent reactors and fuel.) That said, one mussn't forget that coal also gets massive subsidies, if only in the form of permission to engage in environmental degradation and pollution.
Note that all mining is environmentally destructive, and it is rare for the costs of that destructuion to be included in the cost of the products of the mining. So it's quite difficult to come to a rational balance of which technology is more expensive. Fusion has the problem that it's less dependant on mining, so it doesn't get the benefit of free pollution of the environment. This makes it more difficult for it to compete with established technologies. But it's not even nearly ready yet anyway. None of the existing projects have passed the technological break even point, which is a lot easier than the economic break even point.
I think we've pushed this "anyone can grow up to be president" thing too far.
Yes, but with ford sync in it, you will more likely have blue screams of death.
FWIW, perhaps a version of the original "Project Orion" which propelled the ship by exploding nuclear explosives behind it could be built, but that would be a lot easier to design with fusion explosives than with fusion explosives. Gramted that fusion explosives would probably be less polluting, and thus could be used closer to an inhabited planet (or space station?).
Even if ground based fusion reactors turn out to be cheap and simple in the near term, I have severe doubts about thier suitablitity for powering a spaceship until a LOT more development is done. Before the end of the century wouldn't surprise me. Before 2030 would.
That said, I disagree with the basic premise, that such capabilities are necessary (though they would certainly be advantageous). From my viewpoiint we need to be doing work on long-term closed cycle ecologies. With that capability we wouldn't need fast transport. So ion-rockets would be perfectly suitable for orbit-to-orbit movement, and some kind of skyhook (probably not a space-elevator, but something much simpler, like a pinwheel) for orbit to near planet movement, with the final step made by either a high-flying airplane or a electro-magnetic catapult, depending on the thickness of the atmosphere. This requires some fancy timing for the transfers, but it's something that we could actually build now if we had the commitment...except for the long-term sustainable closed cycle ecology.
I think we've pushed this "anyone can grow up to be president" thing too far.
You can use astronaut poo for shielding.
And on a nuclear ship I'm sure there'd be plenty.
First off, you probably mean neutron instead of neutrino, as the other poster already pointed out. Second, the He3+D reaction produces MeV energy protons which are nothing to sneeze at in an environment intended to confine 10s of keV plasma. Second, assuming you are doing using thermal plasma as in a scheme discussed about here for the engine, you would have significant D+D reactions too which would produce a bunch of neutrons. And it doesn't take much unless you have some distance between the reaction and you, as there are plasma experiments now that can produce dangerous amounts of D+D neutrons even without being anywhere near useful amounts of fusion power being produced.
Little pink fairy wings and pixie dust could power us to mars too, but neither of those is a very practical solution today either.
Per unit of energy produced in raw reactions, fusion produces 3-5 times as many neutrons as fission of uranium. And depending on how you are using the energy, the amount of energy you get from the process may require much more fusion than fission. In fission, some 90+% of the energy goes into the kinetic energy of the nuclei which then becomes heat in the very immediate area of the reaction. In fusion, for example D+T reaction, some 80% of the energy goes into the neutron, which will carry the energy some distance away from the reaction. For a reactor, this is fine, as that 80% is the energy scooped away to make electricity via heating the area around the reactor, but for a rocket engine, much of that may represent lost energy (other reactions have their own significant portion converted to high energy neutrons or protons that may only partially give energy back to the reaction). Additionally, there is secondary radiation from all of those neutrons being absorbed into structure and equipment near the reaction.
One of the main differences for use in a reactor on Earth comes down to the difference between waste produced by fusion and fission. With fusion you have more flexibility and choice what kind of radioactivity is produced by careful control what material is used to make the reactor. You can choose materials that will become short lived radioactive waste that is easier to manage than the radioactive byproducts of fission. For a rocket though, this may not matter as the engine would not be running for decades and could be dumped some place as a whole where it couldn't contaminate Earth. What would matter instead would be the energy efficiency, the specific impulse, and the practical concerns of radiation produced while running (as opposed to longer term waste).
All of the fusion projects that I'm aware of are not only heavy, they're also delicate, and require lots of skilled technical attention.
All of the ones I've worked on were quite robust and solid for the basic structure, as they basic plasma is created and managed with not much more than just a large vacuum vessel, magnets and some power supplies or capacitor banks. This is to the point no one would bother with ladders half the time, because the large bolts and plates on the vacuum vessel turned it into essentially a giant jungle gym that let you get to wherever you needed to on the machine. What tended to be really fragile on the other hand were a lot of the diagnostics, especially stuff like precision optics for spectroscopy or laser based diagnostics, imaging diagnostics, x-ray diagnostics, probes that were stuck into the plasma and shielded with ceramics. But an operating machine would not need 90+% of the diagnostics, and can probably get by on things like magnetic diagnostics that can be made rock solid. I think you could probably go at some of the machines with a sledgehammer, and as long as you avoided the windows on the vacuum vessel and the diagnostics, it would take you a while to do any actual damage.
About the only exception might be some of the heating techniques being used, although those are mostly only relevant to getting steady state reactors going. And those consist of things like high power RF, which the military has some experience with making resilient, and things like neutral beams which would be on par with ion engines that we've already tested in space.
And from your other comment:
Even if ground based fusion reactors turn out to be cheap and simple in the near term, I have severe doubts about thier suitablitity for powering a spaceship until a LOT more development is done.
Assuming there is a demand and hence money for development, I would expect fusion engines to be developed long before ground based fusion reactors are made practical. There are much fewer constraints or much looser constraints for using fusion as propulsion than as a primary source of energy. If you view it as a process for converting electricity into propulsion, you can get by with a lot less efficiency than something that is trying to produce electricity through inefficiency conversion and additionally kept itself going. Because you don't have to worry about contaminating your environment, you have a lot more flexibility and choice in construction materials, and don't need designs that are meant to last decades. The only additional constrain would be worry about mass, but then you at least don't need a whole vacuum vessel and all of the vacuum equipment.
Actually that is fairly well controlled.
A stable system is not inherently a controlled system. There's a big different in control of the Sun between "I put my sunglasses on" (which just controls the little bit of solar power that falls on you) and "I use the Hand of Omega to increase solar output by 0.1%" (which is controlling the entire Sun).
A practical fusion rocket engine is only 30 years away!
Thanks for providing some clarity. What if we're not depending on the actual fusion reactor for motive force? Heinlein's torchships, as I recall, use the fusion energy to heat reaction mass (usually water) to something approaching plasma. The fusion reactor in this concept exists to provide heat, not motive force, which is provided instead by the reaction mass. This allows the reactor to have something closer to the configuration of a power plant rather than a rocket engine.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
In the long run, that might provide more efficiency on a smaller scale, but on the short run, it might be much more difficult. Using fusion as described in the article seems to combine the best parts of working in space, e.g. no neighbors and minimal neighboring equipment, and the best parts of fusion, a lot of energy, in a way that doesn't need a complicated stead state confinement method. Using fusion instead to produce electricity may end up focusing more on the negatives of both being in space, mass & size constraints, and fusion, e.g. getting it to work and efficiently produce power. The collection of power and/or heat in the latter case might be difficult too, depending on how much volume that heat is spread out over.
I would expect fusion based rockets as outlined in the article could be achievable much sooner than more generic power or heat generation from fusion reactors, assuming there is interest in actually developing it.
Here is a video of a scientist named Charles Chase who works for Lockheed Martin Skunkworks. The presentation is made at Google's "Solve for X". The video is 14 minutes long so I'll give an executive summary. Chase claims that his team has made a breakthrough in developing a small fusion reactor that will lead to a 100MW reactor the size of a truck trailer and of the complexity of a jet engine. The prototype they have built is a cylinder 1m in diameter by 2m long. In their experiment they put deuterium gas into a magnetically confined space and heat it up with radiofrequency energy. He infers that the confined plasma is reaching the conditions necessary for fusion to occur. The reactor is "high beta", with "beta" referring to the ratio of the magnetic field pressure to the pressure of the plasma pushing out. He says that the magnetic field strength in the reactor increases as you go out from the centre of the plasma, thus creating an extremely effective plasma confinement. He contrasts this with a Tokamak reactor, where the magnetic field is generated by the moving plasma itself, and thus decreases in strength out from the centre of the plasma. He says that this decreasing field strength is the main problem with Tokamak reactors and that it causes the confinement to be unstable. If the confinement becomes unstable, the magnetic field decreases, thus creating a negative feedback loop. This contrasts with his reactor design, that tends to create a far more stable plasma confinement.
I have a background in physics and what this man says in his video makes sense to me. It is of course short on details, but what would you expect for a short presentation. And you wouldn't expect a Skunkworks scientist to publish information in the same way as a university scientist. I have often puzzled in the past as to why we can't use an elegant method of magnetic confinement to achieve the conditions for fusion on a small scale. Tokamak seems an inelegant dead end. I think that if you can adequately confine the plasma, you have solved the energy balance problem that has plagued fusion reactors in the past.
Watch the video and see what you think.
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Steal from Keshe Technologies freely dispursed USB stick much?
Old Old news.
Old Old news.
Think of it as a super high density fuel that just takes a lot of energy on the ground to process.
It doesn't even have to be exothermic (net energy gain) on the spacecraft, without considering any ground processing. In other words, it's perfectly fine if, for each kWh of electric energy you supply into the engine, you only get e.g. 0.4 kWh of kinetic energy of exhaust gases (plasma) coming out of the engine's nozzle. What's much more important is that the engine puts that 0.4 kWh into a very tiny amount of plasma, so that the plasma's velocity is very high (for a given amount of kinetic energy, the velocity is proportional to the reciprocal of the square root of the mass). That velocity is the "specific impulse" of the engine, and it determines how much fuel mass you need to achieve a given delta-v of the vehicle.
Actually, thinking about it for a minute, a hydrogen bomb is a bad comparison. What this idea is closer to is a Farnsworth Fusor. For those of you who haven't heard of those, click the link. Short version: we can very easily make a device that causes fusion to happen, in a controlled non-explody way, provided we aren't too concerned about breaking even on energy. And fusors date from 1964, just to give you an idea of how long the tech has existed. There are even homemade ones in existence.
Achieving fusion is easy. Making fusion POWER PLANTS is hard.
Since the object of the exercise is propulsion, rather than power, the usual objection to fusion need not apply. Doesn't matter that it takes more energy than it could turn into electricity as a powerpant; an ion engine isn't a viable source for power, but we already use those on probes. What matters is how much reaction mass you have to carry to get where you're going. A fusion engine with a solar or fission power source could outperform conventional rockets on specific impulse and outperform ion engines on pure thrust.
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"We can't solve problems by using the same kind of thinking we used when we created them." - A. Einstein
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Oh yeah, and what do you use for powering the magnetic field to contain the plasma?
Does space-rockets require to be operated in an ocean of fuel (oxygen)? There is a reason we don't use gasoline in space.
Oh yeah, and what do you use for powering the magnetic field to contain the plasma?
The design proposed here uses inertial confinement and pulsed (rather than continuous) operation.
Fission rocket could get to Guam.
... and old news (ancient in fact), will get you a free ticket to "No shit'sville".
The idea of using either fusion OR fission as a rocket "fuel" is nearly as old as the theiories of fusion and fission!
Some atomic rockets engines have even been tested. What's kept them out of space has been the attempt to proactively demilitarise space (to keep weapons out of space, especially nuclear weapons), and a fear of radioactive materials falling out of orbit for whatever reason, into your back yard.
THINK! It's patriotic
i hardly dare comment here since it's way out of my comprehension but the advantage here would be the reduction in mass as a whole then so with the same amount of fuel (in volume) a rocket could go a lot further (or deeper) into space instead of achieving greater speeds to get further faster or is it a little bit of both ? I suppose its not quite jumpgate technology yet ?
Free speech was meant to be free for all... how can anyone grow up in a nanny state ?
You'd get more energy out of a kilogram of this fuel than you would with a kilogram of, say, hydrazine and oxygen.
That means you can either:
1. Keep the total energy the same but launch with less mass (cheaper launch, better acceleration in orbit as you have less mass to move around)
2. Keep the same launch mass but bring along more energy (same or more expensive launch (increased volume?), more fuel to orbit so more endurance)
You'd need to do a much deeper analysis and have actual numbers to figure out what would get you farther, though. It could well be that the reduced mass means you have to expend less fuel to make the trip - OR it might not, and you'd need the extra fuel to make the trip instead.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
Yes, but how is that relevant? The point I was making is that you do your converting of X into YX on the ground, and then you do not need to carry around that extra 2 gallons of fuel.
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-