What role do magnetic fields play in space weather?
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How's the space weather today? Quiet enough for a safe trip to the moon? Quiet enough to operate your GPS navigation system accurately? So active that it would crash your power grid? Like our everyday weather, space weather can change suddenly, become violent, and interfere with our lives.\n\nSpace weather is driven by the sun. The solar wind, a plasma of protons and electrons, streams out of the sun and changes the shape of Earth's magnetic field.\n\nNear Earth's surface, this field is like the field of a giant bar magnet, as shown. \n\nFurther out in space, the streaming solar wind flattens the field towards the sun and forms a long tail pointing away from the sun, as shown. This region where the solar wind and magnetic field interact is called the magnetosphere.\n\nThe magnetosphere traps particles from the solar wind. This complex system responds strongly to changes in the sun's surface, especially to sunspots, which follow an eleven-year cycle. Sunspots can produce large solar flares, bursts of electromagnetic radiation, and outpourings of charged particles called "coronal mass ejections." Changes in space weather result, sometimes with devastating effect.\n\n    August, 1972: During the time of preparation for Apollo 17, a violent solar flare produced intense radiation that would have killed the astronauts had they been in space at that time\n\n    March, 1989:\n\n        * Vivid auroral displays extended as far south as Arizona\n        * Electric power was knocked out in the province of Quebec for nine hours\n\n    January, 1997: A communications satellite failed a few hours after a coronal mass ejection smashed into the magnetosphere.\n\nJust as with our ordinary weather here on Earth, physicists make measurements and build models to understand and predict space weather. Accurate predictions can help protect power and communications systems and enable astronauts to avoid dangerous conditions in space.\n\nNote: 1989, the year of the Quebec blackout, was a maximum in the eleven-year sunspot cycle. On the other hand, 1972, the year of the solar flare mentioned above, was near the sunspot minimum, but in fact flares can in fact occur at any time during the solar cycle.
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Associated with sunspots are often coronal mass ejections (CMEs) which are huge bursts of particles.  If the CME is aimed at the earth the influx of particles warps the shape of the earth's magnetic field and also causes aurora, can damage satellite electronics, and can induce huge currents in electrical lines causing blackouts.
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Many charged particles are sent toward the earth from the sun and they interact with the earth's magnetic field to form the Auora Borealis and other interactions with the Van Allen Belt.
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Here are quite a few articles on what we know so far:\nhttp://www.google.com/search?hl=en&q=solar+flares+site%3Asciam.com&btnG=Google+Search\n\nThe short answer is that magnetic fluctuations create imbalances that allow sunspots to form and for flares to arc from the sun.
1182824
I don't think so. The Earths magnetic field is generated by the dynamo effect of the solid Ni-Fe core spinning at a different rate to the liquid Ni-Fe core around it. I can't see how humans can effect that process.\n\nI guess it might be possible to modify the magnetic field locally be producing another field that interferes with it....but I doubt we're doing anything strong enough to do that. The polar shift of the magnetic field is a natural process that has occurred thousands of times.\n\nTo answer 'my girls' question...the earths magnetic field protects us rather than harms us. If it didn't exist, we'd have little protection against the harmful radiation produced by our sun.
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Yes, if the magnetic field disappeared, there would be more radiation reaching the earth and this would cause adaptations to occur.  There's been some research into what has happened to plants and animals around the Chernobyl nuclear power plant in Russia that melted down and is still leaking radiation.\n\nNow, given that magnetic fields diminish and become spotty during magnetic pole reversal, some adaptation may occur but I'm not sure it will cause wholesale adaptation events.  These reversal events have occured about once every 5,000 to 50,000,000 years and larg land animals have survived for hundreds of millions of years so, yes, I think that they might be able to adapt quickly enough during some periods of low to no magnetic field.\n\nAlso, I think that ocean life will go relatively unaffected because water will help absorb some of this radiation.\n\nHowever, I'm sure some biologist or someone with greater knowledge than myself in this area will come along and prove me wrong. :^)\n\n-- \n\nAfter posting this, I read an article in March 2006 Scientific American on the problems of cosmic rays with respect to interplanetary space travel.  They noted in the article that it is a misconception that the magnetic field is the most significant form of protection from cosmic rays -- that it is the atmosphere itself that provides the greatest source of protection from cosmic rays.\n\nhttp://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=000D6A37-E75F-13F5-A75F83414B7FFE9F
847308
It's a bit complicated.  The Earth's magnetic field is powerful enough to minimize charged particles from the solar wind, and the atmosphere attunates almost all other particles.  However, when a star goes nova, two jets are created at the poles.  These jets are extremely powerful with respect to the rest of the explosion.\n\nTherefore, if the Earth were not in the line of sight of the jets, the atmosphere and magnetic field would be extremely effective, and a supernova would have to be with a few 10s of light years to be dangerous.  However, if the Earth were in a line of sight of the jets, then during a few seconds the Earth could be bathed in deadly radiation, even if the source were a thousand light years away.
950044
In high-energy physics, medical treatments, and space detections, quadrupole field distributions and sextupole field distributions are often required over a large spherical volume. Traditionally, these fields can be generated with cylindrical magnets. In comparison with cylindrical magnets, the spherical magnets have the advantages of smaller values of inductances, lower energy storage, and less magnetic flux leakage. The basic method derives from the target field approach that has been used to solve many of the inverse electromagnetic problems. \n\nCalculation:\n\nThe geomagnetic poles or geocentric dipole, can be computed from the first three Gauss coefficients from a main field model, such as the WMM or IGRF. Based on the current WMM model, the 2005 location of the geomagnetic north pole is 79.74°N and 71.78°W and the geomagnetic south pole is 79.74°S and 108.22°E. \n\nThe magnetic poles or dip pole are computed from all the Gauss coefficients using an iterative method. Based on the current WMM model, the 2005 location of the north magnetic pole is 83.21°N and 118.32°W and the south magnetic pole is 64.53°S and 137.86°E.\n\nThe location of the center of the eccentric dipole, sometimes known as the magnetic center, computed using the first eight Gauss coefficients for 2005.0, is at approximately (r, φ´, λ) = (552 km, 22.2°N, 141.6°E). \n\nThe task of locating the principal magnetic pole by instrument is difficult for many reasons; the large area over which the dip or inclination (I) is nearly 90 degrees, the pole areas are not fixed points, but move tens to hundreds of kilometers because of daily variations and magnetic storms, and finally, the polar areas are relatively inaccessible to survey crews (map of North and South polar wander - courtesy of Dr. John Quinn, U.S. Geological Survey retired). The Geological Survey of Canada keeps track of the North Magnetic Pole, which is slowly drifting across the Canadian Arctic, by periodically carrying out magnetic surveys to redetermine the Pole's location. The most recent survey, completed in May, 2001, determined an updated position for the Pole and established that it is moving approximately northwest at 40 km per year.
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They shot 'em up there with a bar magnet on board.\nThe magnets are in parallel to the earth's north and south \nmagnetic poles.\nAs you know, like charges repel and I'm sure you've had a magnet to \nexperiment and have demonstrated the effect for your self.\n\nAfter they have collected enough star dust, a servo is engaged and the \nbar magnet is allowed to pivot on an axis to bring it into opposition\nto the earth's magnetic field. Now, there is an attraction and our satellite begins to fall to earth.\n\nBesides gravity, we now have the added force of attraction with the magnetism and our satellite begins to fall at such a speed that small particles in the atmosphere pepper the skin of the craft and it starts glowing red, getting white hot!\n\nOn earth, there is a game-boy operating a joy stick to carefully realign the bar magnet to throttle a dose of repulsion just enough to abate some speed from the craft (so it won't burn up.) Not too much though, else it will skip back out of the atmosphere like a stone across water and maybe, take a funny hop and pop you in the nose while the runner goes around second base and heads for home!
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Magnetic fields are created by movement of conductive materials around electric charge or vice-versa.  This is called induction.  Our Earth's magnetic field is created by the rotation of our mostly iron core (induction).  That field protects us from harmful radiation from our sun.\n\nTime has nothing to do with magnetic fields.  Time is a dimension, which allows matter to exhibit properties, but can be altered depending on the frame of reference of any given object.\n\nOh, and by the way, creation theory isn't science.  You can't assume a theory is correct and then arrange "evidence" around that theory and call it science.
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First of we have to understand magnetism. All magnetic objects produce invisible lines of force that extend between the poles of the object. An easy way to visualize this is to spread iron filings on a sheet of paper and place a bar magnet under the paper. The iron filings will arrange themselves around the magnet and along the magnetic field lines.\n\nIn the simplest terms, Earth can be thought of as a dipole (2-pole) magnet. Magnetic field lines radiate between Earth's north and south magnetic poles just as they do between the poles of a bar magnet. Charged particles become trapped on these field lines (just as the iron filings are trapped), forming the magnetosphere.\n\nThe origin of the Earth's magnetic field is not completely understood, but it is generally believed to be associated with electrical currents produced by convective effects and rotation in the spinning liquid metallic outer core of iron and nickel. This mechanism is generally known as the dynamo effect. \n\nBecause of the rotating outer core, this then produces an electric current, which in turn, produces a magnetic field that is also known to interact with the fluid motion to create a secondary magnetic field. Together, the two fields are stronger than the original and lie essentially along the axis of the Earth's rotation.\n\nHope this helps you out a little :)
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Sunspots are places where the sun's magnetic field has "kinked" and is poking upward above the sun's surface.  They are darker because they are cooler than the surrounding regions.  The gas is cooler because the magnetic "cork" blocks energy from flowing upward.\n\nThe kinks in the magnetic field happen because the sun is a "ball of gas" and does not rotate at the same rate at all latitudes.  Regions near the equator rotate faster than regions near the poles.  The magnetic field is dragged along, causing it to wind around the sun and developing the kinks which cause sunspots.
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Yes, there is a complex relationship.\n\nThe poles of the Earth's magnetic field actually change their locations across geological time.\n\nHowever, it's speculated that the Earth's magnetic field may be caused by a flow of liquid iron in the Earth's outer core, which might be affected in part, but not only, by Earth's rotation.
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Before we can understand auroras, we need a few facts about the space around our Earth. There are many things in this space that we can't see.\n\nOne thing is the air we breathe, our atmosphere. It is really a mixture of several gases, mostly nitrogen and oxygen, with traces of hydrogen, helium and various compounds.\n \n\n\nA Field of Earth\nAnother thing we can't see is a magnetic field that surrounds the Earth. If you've ever played with a bar magnet and iron filings you've seen the curved patterns the filings form in the magnetic field. The next picture shows how the magnetic field around the earth's core is like the field of a bar magnet.\n\nThe Earth's "magnet" is deep in the core. Since we can't see the magnetic field, we draw lines to represent it. The field lines go into and out of the Earth around the Earth's magnetic poles. Where the lines are closest together the field is strongest. Where they are furthest apart it is weakest. Can you tell where the magnetic field is the strongest? Where is it weakest?   \n\n\nCharged Particles\nA third invisible thing in the space around the Earth is a plasma, made of lots of charged particles. There are always electrons and positive ions in the surrounding magnetic field. Charged particles in a magnetic field move in a special way: they are guided by the field. The particles travel along magnetic field lines as if they were wires, circling around the lines in a long spiral as they go. Charged particles are the "ammunition" of an aurora.\n \n\nSolar Powered Display\nThe short answer to how the aurora happens is that energetic electrically charged particles (mostly electrons) accelerate along the magnetic field lines into the upper atmosphere, where they collide with gas atoms, causing the atoms to give off light. But why does that happen? To find the answer, we must look further away, to the Sun. The spectacular, "great" auroras in "What do they look like?" are powered by what is called the solar wind.\n\nThe Sun also has an atmosphere and a magnetic field that extend into space. The Sun's atmosphere is made of hydrogen, which is itself made of subatomic particles: protons and electrons. These particles are constantly boiling off the Sun and streaming outward at very high speeds.  Together, the Sun's magnetic field and particles are called the "solar wind."\n\n This wind is always pushing on the Earth's magnetic field, changing its shape.  You change the shape of a soap bubble in a similar way when you blow on its surface. We call this compressed field around the earth the magnetosphere. The Earth's field is compressed on the day side, where the solar wind flows over it. It is also stretched into a long tail like the wake of a ship, which is called the magnetotail, and points away from the Sun.  \n\nSqueezing the Earth's magnetic field takes energy, just the way it takes energy to compress a balloon with air in it. The whole process is still not fully understood, but energy from the solar wind is constantly building up in the magnetosphere, and this energy is what powers auroras.\n\n\nThe Big Push\nSo we have the Earth's magnetosphere, with the solar wind squeezing the magnetosphere and charged particles everywhere in the field. Solar particles are always entering the tail of the magnetosphere from the solar wind and moving toward the Sun. Now and then, when conditions are right, the build-up of pressure from the solar wind creates an electric voltage between the magnetotail and the poles, like the voltage between the two terminals of a battery. It can reach about 10,000 volts! \n\nThe voltage pushes electrons (which are very light) toward the magnetic poles, accelerating them to high speeds, much like the electrons in a TV picture tube that accelerate to hit the screen. They zoom along the field lines towards the ground to the north and south, until huge numbers of electrons
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The magnetic field comes from the magnets that are in the generator. The magnets surround the wire coils. As the wire coils rotate, they pass by the magnets. A moving magnetic field (it's all relative, the magnetic field is still in this case) cause a current to be induced in the wire coils, thus producing electricity.\n\nI don't it has much to do with the earth's magnetic field.
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Eric Jaffe-Magnetic Thrust: Fields force matter into black holes\n\nLike a child scared to dive into a pool, cosmic matter needs one last push to plunge into a black hole. New observations confirm that magnetic fields provide this final galactic shove. \n\n The observations come from a system in the Milky Way called GRO J1655-40, which consists of a black hole and a normal star. Gas from the star is pulled toward the black hole, where it forms what's called an accretion disk. Angular momentum—the same property that keeps Earth from diving into the sun—keeps the disk revolving around the black hole instead of falling into it. \n\nUnless something knocked them off course, the gases in the disk would continue to circle the black hole forever. "To get matter in toward the black hole, we have to change the orbits in the disk," says study leader Jon Miller of the University of Michigan in Ann Arbor. Until now, scientists weren't sure whether magnetic fields, radiation pressure, or heat alter the orbit and trigger that fall. \n\nUsing NASA's Chandra satellite observatory, Miller's team collected data on X rays emitted from the J1655 system. They found that the X rays came from a wind blowing from the disk, so some force must propel the wind past the black hole's gravitational pull. After simulating the wind on a computer, the researchers conclude that only magnetic fields could create such a force, they report in the June 22 Nature. \n\nThe team had ruled out a wind fueled by heat from the core of the disk or by pressure from radiation blasting out of the disk. A heat-driven wind would have been hotter than the one that the researchers observed, and radiation pressure is too weak to drive that wind. \n\n"Magnetic pressure really was the only viable means remaining," Miller says. \n\nSuch pressure could upset the gas disk's orbit in two ways. The magnetic fields could push the wind outward like a spring, or the force of the spinning disk could fling the wind away from the disk's center. Either disruption of the disk's orbit would cause some matter to spiral downward. \n\nMiller's team appears to prefer the first scenario, says Roger Blandford of Stanford University. Blandford prefers the second, which he describes as an organized magnetic slingshot. "I suspect there are different answers in different types of systems," he says. "But on the face of it, this looks like a big advance observationally." \n\nThough most astrophysicists expected magnetic fields to play a role in black holes, the finding is "very important evidence that what we thought before makes sense," says Avi Loeb of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "It's the first time there's clear evidence for wind coming off an accretion disk." \n\nThe finding could help astrophysicists understand the complex give-and-take between galaxies and black holes,
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Electromagnetic waves are non-mechanical waves that are composed of electric waves and magnetic waves, both products of electric and magnetic fields. They are able to propagate through space (without medium) due to the dependence of electric fields to magnetic fields and vice versa. Electric fields serve to reinforce magnetic fields and they, in turn, reinforce electric fields. This reinforcement is the reason why electromagnetic waves can travel space without a medium.