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Have you ever seen static electricity cause a spark of light?
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What is that spark?
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What about lightning,
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the Northern Lights,
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or the tail of a comet?
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All of those things, and many others,
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in fact 99.9% of the universe, are made of plasma.
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Plasma is a state of matter
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drastically different from the more familiar forms.
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Take ice, for example.
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Ice, a solid, melts to become water, a liquid,
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which, when heated, vaporizes into steam, a gas.
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Continued heating of the steam at a high enough temperature
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causes the water molecules in it to separate
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into freely roaming hydrogen and oxygen atoms.
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With a little more heat, the ionization process occurs
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and the negatively charged electrons escape the atoms,
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leaving behind positively charged ions.
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This mixture of freely roaming negative and positive charges is plasma,
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and at a high enough temperature, any gas can be made into one.
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These freely moving charged particles behave very differently
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from the particles in other types of matter.
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When a doorknob, a solid, has static electricity on it,
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it doesn't look or behave any differently.
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And with the exception of a compass or other magnetic object,
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we rarely see matter respond to a magnetic field.
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But put a plasma in an electric field or magnetic field,
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and you'll get a very different reaction.
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Because plasmas are charged,
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electric fields accelerate them,
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and magnetic fields steer them in circular orbits.
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And when the particles within plasma collide,
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or accelerated by electricity or magnetism,
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light is generated,
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which is what we see when we look at plasmas
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like the Aurora Borealis.
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Plasmas aren't just beautiful, celestial phenomena, though.
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Imagine a tiny cube made of normal gas with a very high voltage across it.
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The resulting electric field
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pushes some of the electrons off the atoms and accelerates them to high speeds
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causing the ionization of other atoms.
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Imbedded impurities in the tiny cube of gas
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cause it to gain and release a precise amount of energy
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in the form of ultraviolet radiation.
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Attached to each tiny cube,
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a fluorescent material glows with a specific color
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when ultraviolet light at just the right intensity reaches it.
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Now, make a rectangle out of a million of these tiny cubes,
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each separately controlled by sophisticated electronics.
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You may be looking at one now.
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This is called a plasma TV.
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Plasmas also have implications for health care.
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Plasma chemists create highly specific plasmas
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that can destroy or alter targeted chemicals,
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thereby killing pathogenic organisms on food or hospital surfaces.
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Plasmas are all around us,
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in forms that are both spectacular and practical.
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And in the future, plasma could be used
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to permanently rid landfills of their waste,
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efficiently remove toxins from our air and water,
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and provide us with a potentially unlimited supply
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of renewable clean energy.