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World's Strongest Magnetic Field Is Demonstrated

lazarus_ writes "PORTLAND, Ore. -- Researchers at Florida State University's National High Magnetic Field Laboratory in Tallahassee achieved the holy grail of magnetism recently when their high-temperature superconductor attained the coveted 25-Tesla field strength record."

55 comments

  1. Southern Metalhead Population Devastated by robdeadtech · · Score: 5, Funny

    Metalheads from as far south as Miami, as far north as Atlanta, and as far west as Memphis were seen hurtling through the air at breakneck speed headed toward the city of Tallahassee.

    Tampa, known for it's unusually dense Death Metal population, was particularly hard hit.

    --
    Heil Sig! -Rob
    1. Re:Southern Metalhead Population Devastated by vbweenie · · Score: 1

      Ironically, hair-metal band Tesla were unaffected, due to their having abandoned electrical instruments during the making of their album Five Man Acoustical Jam...

      --
      Experience is a hard school, but fools will learn no other.
    2. Re:Southern Metalhead Population Devastated by hondo77 · · Score: 1

      Metallica, to nobody's surprise, was unaffected.

      --
      I live ze unknown. I love ze unknown. I am ze unknown.
    3. Re:Southern Metalhead Population Devastated by Anonymous Coward · · Score: 0

      Are there any more metal heads in america?

  2. Don't connect ohmmeters to superconducting magnets by G4from128k · · Score: 5, Insightful

    I worked at a place about 17 years ago that was using a superconducting magnet (3-5 T) and the "owners manual" expressly forbade attaching an ohmmeter to the magnet coil to see if the coil had become cold enough to superconduct. The problem was that at even low milliampere currents, the coil could store about as much energy as a photographic flash capacitor. Disconnecting the ohmmeter could create a nasty zap and possibly create a damaging arc inside the coil.

    The field was quite fun if you didn't care about your credit cards. You could feel the eddy current drag on a penny if you moved it in the field and copper rings would fall in slow motion.

    Ah! The good old days!

    --
    Two wrongs don't make a right, but three lefts do.
  3. Ok by squiggleslash · · Score: 0, Flamebait
    I assume it's not really the world's strongest magnetic field, or that what's meant is the world's strongest magnetic field covering a certain, small, area that isn't the whole Earth.

    I mean, if it really is the world's strongest magnetic field, then presumably compasses all over the world massively malfunctioned when it was turned on.

    --
    You are not alone. This is not normal. None of this is normal.
    1. Re:Ok by andfarm · · Score: 1

      It *is* stronger than the Earth's magnetic field at its source. The issue is that magnetic fields drop off by the inverse cube of the distance, IIRC, making this superconducting magnet's range of effect to be quite limited. It *will* mess up compasses, but only *very* nearby ones.

      --

      TANSTAAFI: There Ain't No Such Thing As A Free iPod.

    2. Re:Ok by njchick · · Score: 2, Informative
      Magnetic flux density is local by definition and it's measured in Tesla. Magnetic field of Earth is 1/20000 Tesla. Jupiter has magnetic field measuring 1 Tesla in some locations. The Tallahassee magnet produces 500000 times stronger field than Earth.

      Magnetic flux is magnetic flux density multiplied (or integrated) by the surface. The unit of magnetic flux is Weber. That's where Earth wins over all man-made magnets.

    3. Re:Ok by PurpleFloyd · · Score: 5, Informative

      No, this is the largest magnetic field ever created (that we know about), although it does cover a fairly small area. The Earth's magnetic field is weak but very, very large; magnetic fields drop off rapidly (Inverse cube of distance, if I recall correctly) as you move away from the source. Similarly, speaker magnets are fairly weak (on the order of a few hundred to a thousand gauss) but since they are large, they affect a greater area than a small rare-earth magnet that has a 1 Tesla (10,000 Gauss) field strength - a few meters away, the magnetic field is lost in the "background noise" of the Earth's magnetic field. While this is almost certainly smaller than a tiny rare-earth magnet, it still won't cause compass needles all over the Earth to point in funny directions; just those around the building it's installed in. In summary: powerful magnet != big field.

      --

      That's it. I'm no longer part of Team Sanity.
    4. Re:Ok by Anonymous Coward · · Score: 0

      Don't confuse "world's strongest magnetic field" with "strongest world-wide magnetic field". If we wanted to mean "strongest world-wide magnetic field" we would have written "strongest world-wide magnetic field". We write what we mean, and we mean what we write. That's how language works. So assume we write what we mean, and assume we mean what we write. Thanks.

    5. Re:Ok by PurpleFloyd · · Score: 1
      While this is almost certainly smaller than a tiny rare-earth magnet, it still won't cause compass needles all over the Earth to point in funny directions; just those around the building it's installed in.
      Sorry, I meant to say that the big magnet is bigger than a little rare-earth like you might find in your hard drive.
      --

      That's it. I'm no longer part of Team Sanity.
    6. Re:Ok by mshiltonj · · Score: 1

      Magnetic flux density is local by definition and it's measured in Tesla. ... Magnetic flux is magnetic flux density multiplied (or integrated) by the surface.

      OK, but how does the flux capacitor fit into this?

    7. Re:Ok by Anonymous Coward · · Score: 0

      Where the sun doesn't shine, for that comment...

    8. Re:Ok by Proudrooster · · Score: 1

      Don't magnetic fields drop off at the inverse SQUARE of the distance or does that only apply to light (eletromagnetic radiation) and gravity?

  4. Side Effects by kurosawdust · · Score: 1, Funny
    Why do I get the feeling that the following scene will be rather common among the professors present at this event:

    Clerk:"Uh, Sir, the American Express card didn't work either. All of your credit cards are totally blank."
    Scientist Guy: "Son of a BITCH!"

    SCIENTIST GUY then proceeds to consciously attract a crowbar from the Crowbar Aisle to his hands via his newfound magnetic powers and beat CLERK senseless.

    ok maybe not that last part though...

    1. Re:Side Effects by ColaMan · · Score: 1

      Most terminals allow you to manually key in the digits of a card , so even with a bad stripe you can still get lunch.

      --

      You are in a twisty maze of processor lines, all alike.
      There is a lot of hype here.
  5. Old news actually... by IpsissimusMarr · · Score: 1

    While I'm proud of my university this is quite old news. The Lab email announcing this is dated August 23rd. And this has been on ./ before in a slightly altered form: FSU Sets 7 World Records In High Magnetics Research
    Of course its still a damn neat achievment.

    --
    "Engineers do the work of man, Physicists do the work of God"
  6. Where's CleverNickName when you need him. by Elwood+P+Dowd · · Score: 1

    Wesley: Careful with that. It'll rip the iron right out of your bloodstream.

    (P.S. I couldn't find the exact quote online. But I did discover that there is no more depressing thing than ST Voyager based fan fiction. Some of them have completely perfected the stilted dialog. Eugh.)

    --

    There are no trails. There are no trees out here.
    1. Re:Where's CleverNickName when you need him. by Elwood+P+Dowd · · Score: 1

      Ack. According to this dude, it isn't Wesley that says it. It's some romantic interest talking to him:

      "Careful. That'll suck all the iron out of your bloodstream."

      Always struck me as hilarious bullshit. Anyone know if that's possible? Is the iron in your blood polar and magnetic, or is it part of some larger molecule?

      --

      There are no trails. There are no trees out here.
    2. Re:Where's CleverNickName when you need him. by GISGEOLOGYGEEK · · Score: 1

      The iron in your blood can not be pulled magnetically like that because it is combined with other elements in the hemogloben molecule and not magnetic at all in this form.

      This is why all sellers of those magnetic bracelet scams that claim their magnets pull blood to areas with poor circulation should be taken out and shot.... as should all the actors on those infomercials that claim they work.

      --
      George Bush + Linux = "I will not let information get in the way of the fight against Windows"
    3. Re:Where's CleverNickName when you need him. by Elwood+P+Dowd · · Score: 1

      Yeah. I figured that. That even occured to me when I first watched the show at the age of 12.

      Further evidence that Star Trek was crappy before Voyager. We just didn't know any better.

      --

      There are no trails. There are no trees out here.
    4. Re:Where's CleverNickName when you need him. by Anonymous Coward · · Score: 0

      But my blood is conductive, so there can be eddy currents. Yes. I know those bracelets are BS, but saying hemogloben is not magnetic doesn't prove it.

    5. Re:Where's CleverNickName when you need him. by Anonymous Coward · · Score: 1, Informative

      One word: hemoglobin.

  7. this article forgot to mention.. by iannn · · Score: 4, Informative

    Creating a 25 tesla magnetic field is not a big deal in itself. People have been using ~ 40 tesla, pulsed magnetic fields to study superconductors for years. There are also techniques to generate 1000 tesla fields (first reference i googled: http://www.intas.be/catalog/94-3569.htm). They last about a millisecond. How? Well basically, by using explosives. While i only skimmed this article, the peice they are probably leaving out is that they are creating 25 tesla magnetic fields over a large area or for a significant amount of time (more than a second or two). This is really useful and takes tons of energy, so it's an achievement worth mentioning. What i don't understand is why the existence of those other magnets is overlooked, especially since the National High Magnetic Field Laboratory collaborates with lots of people who use them.

  8. Re:Don't connect ohmmeters to superconducting magn by jerde · · Score: 1

    Were you ever subjected to fields strong enough that you felt any biological effects?

    Over in another thread I researched a little bit on the known bio-effects of static magnetic fields. I'd be curious to hear first-hand from someone who might have experienced them.

    - Peter

    --
    INsigNIFICANT
  9. Alright lets see some numbers. by roninbix · · Score: 1

    Anybody want to post a couple formulas? How about the ones you'd need to relate 25 tesla's to mass that it could pull or lift. I'd settle for something that translates it to force.

    1. Re:Alright lets see some numbers. by nusuth · · Score: 1

      google for "diamagnetic", "frog".

      --

      Gentlemen, you can't fight in here, this is the War Room!

    2. Re:Alright lets see some numbers. by mdielmann · · Score: 1

      I just want to know what the bill would be if you let go of a (tin Canadian) dime from say, 3 feet away, and if you would survive to get the bill.

      --
      Sure I'm paranoid, but am I paranoid enough?
    3. Re:Alright lets see some numbers. by DrLudicrous · · Score: 1

      This was an actual problem from the Univ. of Illinois Physical Qualification Exam. Given the characteristics of the atoms that make up a frog, you had to calculate the magnetic field necessary to levitate it (i.e. create a force that opposes the gravitational force). Do this in 45 minutes off the top of your head, and you will pass!

  10. Strongest constant magnetic field, perhaps by guybarr · · Score: 2, Informative


    But higher transient fields have been produced for some time:

    Large Z-Pinches routinely reach 100T, and may, at stagnation, quite conceivably reach fields as high as 10^4 T .

    In laser produced plasmas, magnetic fields have actually been measured to rise up to more than 3*10^4 T :
    Tatarakis et. al. Phys. of Plas. 9/5 pp. 2244 (2002)

    --
    Working for necessity's mother.
  11. question, the by Anonymous Coward · · Score: 0

    Okay this may be a silly or stupid question, but you don't have to answer, so: How does the magnetic field actually propagate? Using what particles?

    1. Re:question, the by Patrik_AKA_RedX · · Score: 1, Informative

      Magnetisme is electromagnetic radiation. So its force particle would be the photon.

  12. Biological Effects by G4from128k · · Score: 1

    Sadly, I never noticed any biological effects, but then we did not climb into the center of the solenoid when it was operating.

    What I would like to see is a magnet big enough and strong enough to levitate a person. I'm sure you've seen the levitating frog trick. Now if they could only scale that up because it would be a cool tourist attraction.

    --
    Two wrongs don't make a right, but three lefts do.
    1. Re:Biological Effects by 3waygeek · · Score: 1

      I saw something very close to that, about 2 years ago, in a newsletter from the Iowa State University physics department; they had one of the profs sitting on a disc of superconducting material that was levitating above a superconducting magnet. Imagine a larger version of the first photo on the linked page.

    2. Re:Biological Effects by AllenChristopher · · Score: 1
      Entirely different, of course. The prof wasn't experiencing diamagnetic levitation of his own molecules, but rather levitation of something below him that he sat on in the usual way.

      If the professor were in a very large levitation tube, the magnetic force would be acting on every part of his body uniformly. It's a real gravity-magnetism balanced environment, as you can see here, where the water forms a spherical bubble from water tension.

    3. Re:Biological Effects by treat · · Score: 1
      I'm sure you've seen the levitating frog trick.

      Wouldn't this cause horrible brain damage? I mean, to a mammal, seeing as how we actually use our brains for most stuff. And, you know, the giant, like alien-sized, magnetic field.

      How big a magnet would you need to use as a weapon, anyway?

  13. Speaker magnetic field by xluap · · Score: 1

    Speaker magnets are made of ferrite, and the maximum field of ferrite is about 0.1 tesla (or 1000 Gauss). However, inside the speaker, at the voice coil, the field could be 1 tesla (or 10000 Gauss) because the metal plates on the magnet concentrate the field.

  14. In Other News, by RCO · · Score: 1

    field reporters have found that a large shipment of faulty electronic equipment has also been sent to the area.

    --
    'And all the monkeys aren't in the zoo Every day you meet quite a few...'
  15. Good journalism at work by krysith · · Score: 3, Insightful

    The article, in addition to being a dupe , also calls the director of the NHMFL "Jeff Crow". Last time I talked to him, his name was Jack.

    1. Re:Good journalism at work by Rogerborg · · Score: 1

      But remember, when the FBI come calling for our details, Taco and Cowboy Neil promise to go down fighting, just like Butch and Sundance. Hmm, which one's the Butch and which one's the Bitch?

      --
      If you were blocking sigs, you wouldn't have to read this.
  16. I'm disappointed by jayhawk88 · · Score: 1

    How the hell could we get 30 comments in without an Eric Lensher joke?

  17. Biological effects? by Anonymous Coward · · Score: 0

    Hi. I have a metal (titanium) screw in my leg. If I stood next to this, would I be severely injured?

    1. Re:Biological effects? by AllenChristopher · · Score: 3, Interesting
      I don't think so. Titanium in an of itself is not particularly sensitive to magnetic fields because it is not a ferro-magnetic metal. That's one of the reasons they use it. If, for example, you have a metal screw in your body and now you need an MRI, you'll be in trouble if it's, say, steel. Titanium implants of recent manufacture are generally considered MRI safe up to 1.5 Tesla, I think, and the issues people are concerned about there are generally heating, sometimes induction.

      Still, at 25 Tesla you wouldn't want to get too close. If your screw isn't completely pure, and nothing ever is, the impurities may lead to little bits of it being magnetically affected. That can lead to deformation and such. It's not that you're entirely safe around magnet that big, it's that the screw isn't going to tear out of your bone at splintering speeds, "severely injuring" you.

  18. Another first by Anonymous Coward · · Score: 1, Funny

    World's most screwed up monitor in the office next door.