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Experimental Magnetic Shield Against Cosmic Rays
stiller writes "British scientists from the Rutherford Appleton Laboratory have developed an experimental set-up in which a $20 magnet is used to deflect solar-wind-like radiation." Reader Dersaidin points out a slightly more enthusiastic article at Universe Today which emphasizes the possibilities of systems based on this phenomenon to protect astronauts during solar storms, writing
"It's a good start. Hopefully, later versions will be able to protect spaceships from energy weapons. A beam from the LHC can melt a 500kg block of copper. Shields, check. Energy weapons, check. Now we just need a viable interstellar drive, and an energy source to power it all."
Modulate the shields !!
Yes, I'm left. You have a problem with that?
If dealing with a Bussard ramscoop, of the type seen in e.g. Larry Niven's stories in Neutron Star , wouldn't this kind of protection from radiation also mean deflecting mass useful for propulsion?
Did anyone else misread the title?
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
Make the drive coils out of uranium and power it with allotropic iron.
Of course, you will have to give the ship a good British-sounding name like "The Dentless".
ANd remember to really reinforce the breech shielding on the Q-Gun.
You either believe in rational thought or you don't
Does this remind any one of deflector shields from Scorched Earth?
I suggest mounting a standard generator at the core of the prospective space ship and attaching a coffin containing one of our founding fathers to it. The rapid spinning should provide plentiful power for all manner of techno-gadgetry.
this? http://tech.slashdot.org/article.pl?sid=08/10/27/175258
-Ours is the wisdom of Solomon, the magic of Merlyn, the fall of Icaris.
Anyone else remember that awful sequel?
$nice = $webHosting + $domainNames + $sslCerts
As long as we're not venting drive plasma, we're good to go.
That is, unless somebody left a sweater in one of the warp plasma conduits.
According to TFA this thing uses about as much energy as an electric kettle, Does this mean British astronauts will need to choose between the two? I can see it now, a mustachio'd astronaut (in my mind I imagine him an old RAF captain) hovering over the button and staring at the kettle. Agonizing over the decision before muttering 'To the Queen' and putting the kettle on.
This brings up a larger issue to me...how well does tea steep in zero G, And would there be a difference between an Earl Grey blend or a black tea blend?
-=Bang Bang=-
No, what we need is a strong hull that can withstand all the micro-meteoriods hitting it at 27,000+ mph.
I recommend getting a General Products #2 hull.
/.'s 10 Millionth
Now we just need a viable interstellar drive, and an energy source to power it all.
Then it's all alien babes from here to the farthest star! Warp factor exosex, Scotty, all power to the engines!
Loose lips lose spit.
No hope of becoming one of the Fantastic Four. Bummer.
A beam from the LHC can melt a 500kg block of copper.
Technically, if things are set up, any continuous source of energy can melt just about anything meltable. Just keep the energy flowing, insulate the target, and if the temperature of the energy source (e.g. a lightbulb) is higher than that of the target, then energy will couple in and eventually melt the target. What needs to be mentioned if such a statement is to be of any use, is how long such melting is expected to take.
up next: Monster Gold Diamond HDMI cables with Cosmic Ray protection.
Swap those crystals round, Carter.
According to this CERN page, in the few microseconds that it takes a beam dump to complete. The circulating kinetic energy of the beam is an impressive 350 MJ, equivalent to running a 1000 watt heater for 97 hours.
When the space elevator eventually gets built, passengers are going to need something to protect them from the radiation in the Van Allen Belts. Rather than hauling a bunch of passive shielding up and down, these isomagnetic shields would be pretty useful.
Power would come from the same source that drives the climber (whatever that is...).
The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
I agree with what you're saying.
But what they could be talking about -- something that's actually a useful metric -- is whether the energy source can get energy into a material faster than it can conduct the heat away. It's comparatively easy to drill a hole in a thermally insulative material with a laser, but much harder with copper. So if they want to make an impressive statement, they probably should make it clear (to those of us who care) that this thing can dump energy in, faster than any material can get rid of it, meaning you are guaranteed to vaporize a hole in the material.
Nostalgia's not what it used to be.
Seems like this could also be useful for protecting Earth-based computers from the occasional cosmic ray that makes it through the atmosphere and the magnetosphere. At least, if the magnetic field doesn't interfere with their operation just by itself.
This is an approach that's been worked on for years and years now, and there hasn't been any rapid progress. Electromagnetic shielding may ultimately work, but it has a lot of problems to overcome. Without some kind of significant technological progress, the radiation dose for astronauts going to Mars is a real showstopper: http://en.wikipedia.org/wiki/Health_threat_from_cosmic_rays
Engineers have studied a variety of electromagnetic field configurations for this. Electric fields have a problem because any field that repels positively charged particles will attract negatively charged ones, and vice versa. Also, large DC electric fields tend to discharge violently.
With magnetic fields, one problem is that you need magnet coils that carry huge currents. If they're not superconducting, then you're talking about huge amounts of power, way more than is really practical. If they're superconducting, then you're trusting your life to a type of technology that's notoriously prone to failure; normal superconductors need liquid helium temperatures, which are very hard to maintain reliably, and high-temperature superconductors still need liquid nitrogen temperatures (and also may be decades away from being ready for this type of application).
In this article they talk about using an AC field, although they don't provide many details. One thing I wonder about with an AC field is radiative losses. They say, "The approach will probably also work with a field that is not on constantly, but cycles on and off - conserving the power that is precious on long-term missions." I totally don't get the idea here. They make it sound like they're just going to have it be pulsed, with a low duty cycle. But then won't it only provide some small fraction of the desired protection?
Another approach that looks promising is to make the spacecraft from low-Z materials like plastics; most of the hazard from cosmic rays is actually from secondary radiation (which is why thicker shielding actually *hurts* you, for any practical thickness).
I think the real question to ask is whether there is any valid, objective reason for sending a human to Mars. Crewed spaceflight has never been a good value for the money in terms of scientific research, compared to probes. Or if the motivation is some kind of romantic vision of heroic exploration of a new frontier, then I think we need to be more realistic about the prospects for permanent, economically viable settlements, which are probably at least a century away.
Find free books.
How long does it take for the beam to melt 500 lbs of copper?
.86 microsecond beam burst.
FTA, testing showed a 1.5 mm beam "burnt" 40 meters into a block of copper in 86 microseconds.
So... napkin calculation...
.15 cm * 4000 cm == 600 cm^2.
density of copper is about 9 g/cm^2, so 5600 grams of copper melted per
500 lbs =~ 227 kg, so roughly forty 86 microsecond bursts to melt 500 lbs...
So we're talking roughly 3.5 milliseconds to melt 500 pounds of copper.
We're talking 70 tons of copper melted per second for a single beam per second. That's a hell of a lot of energy, but I'm not sure what the standard unit is for energy/time (hiroshimas is just energy; libraries of congress and football fields obviously don't apply). Anyone know what the standard made-up unit is for energy/time?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
s how long such melting is expected to take.
Presumably, about the time it takes light to travel 27km, since the beam can't be longer than the circumference of the collider and the beam is near light speed.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Hey, we got the Fantastic Four, least according to the movie, because the shields DIDN'T work.
Sorry for the movie spoiler.
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
That is the most amazing engineering article I have read in quite some time.
love is just extroverted narcissism
"Now we just need a viable interstellar drive, and an energy source to power it all."
We just need an interstellar drive now. Oh, that and someone to teach that pink bunny how to pilot the ship, after all, his back is going to be plugged into the warp drive.
-Charlie
the new "in" fashion statement amongst the crackpots will be magnets tied to your head to protect from alien radiation?
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
What needs to be mentioned if such a statement is to be of any use, is how long such melting is expected to take.
That's a very good point, and to answer the question raised by it I RTFAed so you don't have to! Regarding the "dump block" that they use to absorb the LHC beam before it becomes unstable:
Emphasis added. That's one hell of a beam.
BTW, I can't help but recall that the Enterprise D from ST:TNG fires its phasers from a large ring on the saucer section. You can almost imagine the LHC being weaponized and using the same technique that diverts the beam into the dump block to direct it outward towards enemy ships. Though it'd have the rather significant drawback that any damage anywhere on the enormous accelerator ring would take out the weapon. But hey, energy beam!
The enemies of Democracy are
Last time i went to see a prostitute. As she turns out to be a shemale i said: no way! Then she did an anal probe to me.
Good against remotes is one thing. Good against the living?
OK, seriously: this only works against charged particles. Masers/Lasers of whatever frequency, not so much. Pretty serious limitation. - Jeff
reposted from below (with corrections) in the comments, since my comment belongs here in response to your comment:
.15 cm * 4000 cm == 600 cm^2.
.86 microsecond beam burst.
FTA, testing showed a 1.5 mm beam "burnt" 40 meters into a block of copper in 86 microseconds.
So... napkin calculation...
density of copper is about 9 g/cm^2, so 5600 grams of copper melted per
500 lbs =~ 227 kg, so roughly forty 86 microsecond bursts to melt 500 lbs...
So we're talking roughly 3.5 milliseconds to melt 500 pounds of copper.
That's 70 tons of copper melted per second for a single beam. That's a hell of a lot of energy, but I'm not sure what the standard unit is for energy/time (hiroshimas is just energy; libraries of congress and football fields obviously don't apply). Anyone know what the standard made-up unit is for energy/time?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
According to the article, the 1.5mm beam (already diffused from the original 0.2mm beam) can penetrate 40 meters (around 130ft) into solid copper in 86usec.
Anyyone have any numbers on the total exposure
to radiation OUTSIDE and INSIDE airport gates in addition to in-flight exposure?
Thanks for your answers.
Cordially,
Kilgore Trout
"and an energy source to power it all."
Check.
My anus after HomeTown Buffet.
--Toll_Free
Stan Lee has a patent!
Anyone know what the standard made-up unit is for energy/time?
Energy/time is Power. I don't know if there's a standard, but if not I nominate Shuttle Solid Rocket Boosters.
That's ~4.9 GW, btw.
The enemies of Democracy are
http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)
the LHC is not a continuous source. You'll run out of particles in the main ring after about 90 microseconds.
upon the advice of my lawyer, i have no sig at this time
~300 kJ to melt 0.0635 kg (1 mole) of copper.
Did the calcs... roughly 87 MW... not even close to the power of one SSRB.
Can you come up with something a little lestt powerful?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Why cm^2 (square centimeters), not cm^3? It should be 0.15 * 0.15 * PI * 4000 cm = 282 cm^3. so 2544g of copper per 0.86 of millisecond.
This gives 76ms to melt 227kg of copper.
Extreme Programming - Redundant Array of Inexpensive Developers
I would guess 100W lightbulbs would do the job.
350 MJ in 86 us = 4 070 000 MJ in 1 s = 4.07 TW
40.7 billion 100 W lightbulbs.
More than 6 each for everyone on earth.
--
But only for 86 us at a time every 10 hours. I get 10 kW for the mean power requirement assuming it is constantly charging. That is only 100 lightbulbs.
40 years of star trek and you guys are just figuring this out?
Inconceivable! Libraries-of-Congress and football-fields can be made to apply to anything, if you use them right.
Watt? Horsepower? Michael Phelps? NSA datacenter electricity usage? Total solar output?
Elementary my dear: Watts
Believe it or not laptop-miles still applies.
"Hoover Dams" are the units used to represent such things as the power output of the Shuttle main engines. Other popular ones are "enough to light N,000 homes" and "equivalent to N nuclear power stations" (always nuclear, for some reason).
Melting copper takes 13.050 kJ/mol. A mole of copper is 63.546 grams. We'll drop everything to two significant figures, which is probably already more precise than the rest of the numbers. 70 tons is one million moles, so melting 70 tons per second is 13E12 J/sec, 13 terawatts, which is close enough to the 10 terawatt figure for the beam dump that's on the web. Five or six thousand Hoover Dams, then.
power is measured in watts obviously
I was looking for a serious thread to reply to, but it seems this topic attracts more kidding than science. =p
Anyway, my college plasma physics professor, a decade ago, told us that he'd invented the "force field". It created a magnetic shield around an object in a vacuum, and was intended to protect things like satellites from charged particles. (For obvious reasons discussed below he didn't go into detail.)
His work was funded by the U.S. Air Force, who promptly took the patent and classified it. In other words, this was invented about 15 years ago, and this guy might have just made it public, but he's likely not going to get a patent to protect his invention since it will be rejected.
It doesn't hurt to be nice.
This is Robert Winglee's M2P2. He Mini-Magnetospheric Plasma Propulsion. His original idea was to use it as an innovative type of solar sail, but it quickly became obvious that it could be used in the way that these people have stated. All in all, nothing to see here, already been done, and here in the US too. You might also enjoy checking out his page, the guy is a big time plasma nerd.
The world you experience is only a close approximation of reality.
Uh, some math errors exist in some of the parent posts.
A 1.5mm diameter beam that is 40 meters long has a volume given by:
V = pi * r^2 * d
If r and d are in cm, then:
V = pi * (0.15/2)^2 * 400
V = pi * 0.005625 * 400
V = 7.07 cm^3.
At 9 g/cm, this gives a mass of 63.2 grams.
If we're melting/vaporizing this much in 86 uS, that gives a rate of
63.2 / 0.000086 = 734,883.72 g/s (or 1,620.14 lb/s).
It's still a bunch of melted (actually, vaporized) copper, but it's nowhere near 70 tons.
All the above assumes that the beam stays perfectly coherent and doesn't have any losses due to heating of surrounding material. In reality, the beam would rapidly diverge, and heat would begin to flow through the copper. Oh, also, ejected copper plasma would at some point begin to interfere with the beam itself before it reached the copper itself. This would rapidly de-focus the beam and absorb energy, so the plasma ejecta would get oh-my-god hot while shielding remaining copper from being damaged.
Ah, you're referring to the hypothetical z-axis of the third dimension.
Thanks for catching the error.
So it's only about 3 tonnes melted copper per second... still a lot of power.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Considering some types of radiation are not affected or phased by solid materials, it would make sense that in order to deflect it you'd need to create some sort of EM interference, since the radiation exists somewhere in the EM spectrum.
My question is when is someone going to try to patent it? It's a little too obvious to me, and I really have NO experience in the field, so I don't think the idea itself could be patented.
Maybe the designs that accomplish the job, yes. But the idea itself? Let's hope one doesn't try to patent it, since it's really the ONLY method available for radiation protection in this day and age.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
In the amount of time it takes you to read this it would have melted over 200 tons of copper. ... though, I think your math is wrong. :U
Pff! We don't need that! When there's cosmic rays coming, just send 4 astronauts to become the Fantastic Four and start a Golden Age of super-heroes!
I, for one, cannot wait to upgrade my tinfoil hat. It was starting to draw looks because it is so out of style.
If you don't know what you're doing, you can't make mistakes.
Sounds like 1 LHC...
>>Libraries-of-Congress and football-fields can be made to apply to anything, if you use them right.
In power? I propose the imaginary unit of Work being the energy needed to move a Library of Congress across one football field at a rate of 1 ms/s
Since he seems to have progressed just fine over the last twenty years or so, I'd say having all that energy constantly around him hasn't affected him at all. Let the pink bunny do all the extraterrestrial work--radiation hasn't really created a problem. (The real life batteries though never seem to do well in my chargers)
Its about 17.8 million horsepower
Now we just need a viable interstellar drive, and an energy source to power it all
And a human race that can make contact with aliens without being considered a disposable threat.
Seriously, if anyone's watching us out there, they must be real disappointed with us, and I'm not talking about those religious things.
-Billco, Fnarg.com
Yep. Typos...
Multiply everything above by 10.
So, 7.348 Mg or 16.2 k pounds.
About 8 tons.
The energizer bunny, and ... the thing from Event Horizon?
The ship went to a dimension of chaos, and when it came back it was alive. (dum-dum-dum-dum)
obviously you're better in geometry than physics :)
e = mc^2, and the LoC ain't light.
TFA did exactly that. One of them, at least. This one: http://spectrum.ieee.org/aug08/6558
That's pretty significant energy. Admittedly, it's probably a fairly small hole, but it does a good job of explaining why the beam needs to be diffused and scattered as it's being dumped into a block of graphite.
If you believe everything you read, you'd better not read. - Japanese proverb
Waaaay too much. You'll blow the flux capacitor. You only need to channel one point twenty one of them....
If you believe everything you read, you'd better not read. - Japanese proverb
Would like to point out that the Earth's atmosphere is suppose to defect solar-wind radiation naturally; (if it wasn't getting torn apart by pollution). Now if they made a more powerful version of the magnet that would be interesting; we could then redirect meteors and space debris.
we also need the total control of gravity.
A trifle, to be sure.
The Kruger Dunning explains most post on
Assuming it's done the same way.
Of course based on my experience with the military and satellites, it sounds like crap.
The Kruger Dunning explains most post on
IN space weapons have thrust. How much delta v could it pump out I know it weighs alot but just give it time
Too bad they weren't around when the FF were in space...
I'm sure Ben Grimm could have used one of those.
watts = joules/seconds
Just watch out for terrorists trying to take Dylithium Resin!
No, I am not an English major. My posts are subject to typos and incorrect grammar. Do not expect perfection.
The high-power laser systems I've worked with weren't anywhere nearly as intense as this beam, obviously, but the beam dump still cost a fair bit since it was consumable, so we went with cheap. We used a brick set at a very low angle to maximize the surface area exposed to the beam. We'd go through (in a couple meanings of 'go through') a brick a day. Still, cheaper than copper or graphite.
Nostalgia's not what it used to be.
Charged particles are easily manipulated with EM fields so using magnets to "deflect" them is not exactly an "unobvious" application. Of course a bit of engineering will be required to determine how strong the magnets need to be to handle a given level of particle energy.
Now classifying the information just means someone else will have to re-invent the "magnetic deflector" - and will probably get to put their name on it to boot.
You either believe in rational thought or you don't
Won't someone think of the Vogons?
One of the 187.
Most of the research concerning space-based radiation shielding was done under the umbrella of the now defunct Nasa Institute for Advanced Concepts. One proposal, based on "multipole electrostatics" was developed to protect against not only space-borne radiation, but micrometeorites. See the /. story or here
:)
Here's another one that uses some of the plasma ejected from a spacecraft's propulsion system ( eg. VASIMIR ) to set up a huge and extremely powerful magnetic field around the manned section of the spacecraft in order to create a "plasma magnetic shield".
Also, let's not forget that, as one poster mentioned, M2P2 ( Mini-Magnetospheric Plasma Propulsion -- see here ) can be used as a propulsion mechanism whereby it deflects the solar wind and also as a shield against space born radiation. In a nutshell, it operates on the principle of a positive feedback loop wherein initially a magnetic field created by a conventional magnet traps injected ionized helium which itself strengthens the magnetic field which traps even more ionized helium and so on.
It's really sad NASA shut down one of their most promising research institutes. But, all the studies are still there, archived for some interesting reading. I highly recommend it.
jdb2
Anyone know what the standard made-up unit is for energy/time?
Hamsterwheels, I think.
What, you don't think people will respond with awed gasps when you tell them that your doomsday ray has power equivalent to 55 milli-SSRBs?
The enemies of Democracy are
Well yeah I'm pretty sure an SSRB would have fucking destroyed the Delorean, either via excessive thrust or by simply crushing it when you tried to mount the SRB on top...
The enemies of Democracy are
AFAIK Cosmic Rays are EM radiation like very hard X-Rays. They wouldn't be affected by magnetism.
OTOH Solar Wind is charged particles which ARE affected by magnetism.
Just trying to keep the nomenclature straight.
Edwin
Some of modders have absolutely NO sense of humour.
I prefer the "u" in honour as it seems to be missing these days.
We could also use artificial Lunar and Martian magnetospheres to deflect charged particles from approaching the Moon or Mars respectively.
joule is a unit of energy.
from http://en.wikipedia.org/wiki/Joule
One joule is the work done, or energy expended, by a force of one newton moving one metre along the direction of the force. This quantity is also denoted as a newton metre with the symbol NÂm.
joule per second is watt.
from http://en.wikipedia.org/wiki/Watt
The watt (symbol: W) is the SI derived unit of power, equal to one joule of energy per second. It measures a rate of energy conversion.
The standard unit for energy per time is watt (at least for the metric system).
Note to self: When invading Switzerland, hold the copper-armored vehicles in reserve.
"Anyone know what the standard made-up unit is for energy/time?"
i believe it's called a watt.
This discussion seems to be centered around make-believe applications of cosmic ray protection technology... Am I the only Slashdotter using more DRAM modules than spaceships? Granted, my computers' DRAM is protected with ECC, while my spaceships remain vulnerable to "energy weapon" attacks. However, my computers happen to exist.
Thank you, Edward Snowden.
"Arguments from authority are worthless." —Carl Sagan
libraries of congress and football fields obviously don't apply
Well, how about burned libraries of congress per day?
Thought that was the Enterprise Warp Core.
So simply installing a reasonable strong magnetic field will prevent all sorts of nastiness from penetrating the ships hull and causing random mutation. The problem is that high energy neutrons will still be an issue, but the up side is that free neutrons account for an vanishingly small amount of the total ionizing radiation that hits a spacecraft in interplanetary space.
The next shield needs to be about three to six feet of ice around a spacecraft. You can even put interesting things in the water like minerals, sugars, amino acids, all the kinds of things people might need on a long trip in space. This ice shield makes a great replacement for earths atmosphere and provide astronauts with an additional layer of matter to absorb high energy particle from the sun, quasars, active galaxies, whatever. An added bonus is that six feet of water at near absolute zero is a better shield against micrometeorites that a foot of solid steel, and you can't eat or drink steel. The down side is the difficulty of getting the water into space (it would cost an arm and a leg to lift enough water with current technologies), but robotically mining our moon, asteroids, and the the Jovian moons for oceans worth of water should prove perfectly doable.
Finally, you have to provide some artifical gravity, so you spin the craft and make certain there are habitable areas large enough to provide a meaningful angular momentum. The benefit here is that you are keeping the folks inside fit for a planet with a positive gravity, bone that won't break at the slightest touch, and fluid balances that will prevent nasty risk of clotting related health threats. In the area of radiation exposure, rotating the vessel insures that no place in the ship ever get's too much radiation (the tiny amount that get's past the magnetic field and the layer of water that is.)
There is no problem with extensive interplanetary space travel that cannot be conquered with sufficient thought and creativity. There is no sane reason that human being shouldn't be living on the moon and mars by the end of this century. The economic and sociological opportunities should make such an endeavor one of humanities more important.