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nasa's themis mission has overturned a

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long-standing belief about the

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interaction between solar particles and

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the earth's magnetic field

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giant bar magnet

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this magnet forms a protective field

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around the earth shielding us from the

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solar wind that is constantly streaming

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towards earth

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this shield is called the magnetosphere

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the solar wind is primarily composed of

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protons and electrons charged particles

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streaming out from the sun

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some of those particles have very high

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energies radiation energies and they can

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damage astronauts and spacecraft

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we are shielded by our earth's magnetic

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field most of the time however a small

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fraction of the solar wind particles get

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into the earth's magnetic field are

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energized and become the earth's

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radiation belts which can damage

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spacecraft and harm astronauts

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but the sun has a magnetic field of its

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own as well which the solar wind carries

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outwards towards earth

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and the themis spacecraft fleet recently

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observed that 20 times more solar

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particles get into the earth's

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magnetosphere when the sun's magnetic

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field aligns with that of the earth than

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when they're pointed in opposite

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directions

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in the past researchers found that the

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energy from the sun gets into the

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earth's magnetic field during periods

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when the sun's magnetic field points

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southward

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here we found that the particles get in

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the plasma the particles from the sun

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get into the earth's magnetic field when

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the sun's magnetic field points

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northward

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for a long time people have known that

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the location where particles and energy

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get into the earth's magnetic field

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depend on the orientation of the sun's

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magnetic fields but they just hadn't

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realized how many particles get in for

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the northward orientation of the sun's

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magnetic field so what do these new

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findings mean for us here on earth

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well with this new information

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scientists can make better predictions

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about when solar storms will be severe

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meaning we can better prepare for the

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power outages satellite damage and other