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Music

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Alex: Solar flares and coronal mass ejections do

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not always hit Earth. They happen all over the sun and depending

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on where on the sun they occur determines whether or not they're

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going to travel towards the Earth. Phil: Some of them could be shot off to the side, and just miss

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us completely. They could go up, they could go left. Some are

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like curveballs, that a pitcher will throw. They could

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seemingly come straight for us, and then miss us completely.

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Alex: Space weather can have several different effects on the

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Earth and the near-Earth environment. In space, it can create

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dangerous radiation in the form of particles, which is detrimental

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to the health of astronauts. These particles,

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as well as solar flares, can cause cause damage to

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satellites in near-Earth orbit. In addition,

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electromagnetic disturbances created by geomagnetic storms

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can affect power transmission on the ground, can also

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disrupt communication. But space weather has

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no direct effect on human beings themselves. Holly: We are protected

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here on the surface of the Earth from solar flares and coronal mass ejections

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when they impact the Earth, due to the magnetic field of the Earth called the

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magnetosphere, which deflects the magnetic field and the energetic particles

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as well as the atmosphere, which absorbs the higher levels of

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radiation. Phil: Most of the energy that's associated with a solar flare or

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coronal mass ejection doesn't even reach the surface of the Earth. So even

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the biggest of flares isn't going to affect you here at Earth.

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Music. Alex: When a large solar eruption

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occurs, there are generally three things that happen. Each of these takes

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a different amount of time to reach the Earth. The solar flare, because

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it's light, travels at the speed of light and takes approximately 8 minutes to reach

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us. The solar energetic particles are traveling extremely fast

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--close to the speed of light, but not exactly the speed of light--so they take

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roughly 20 to 30 minutes to reach us.

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The coronal mass ejection is much slower, and that takes about

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1 to 4 days to reach us. Music.

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Holly: The sun goes through what we call a solar activity cycle,

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where every 11 years on average, it will go from a very low period of

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solar activity--meaning sunspots and solar storms--to another period

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of low activity, and in-between it goes through what we call solar maximum. At solar

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maximum the sun has a very complicated magnetic field structure, and

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therefore it creates a lot more sunspots and a lot more solar storms like flares,

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and CMEs. It's very important to be able to

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forecast solar events because they can affect our technology, our

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satellites, they can cause power grids to be affected. So as we

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become more and more technologically advanced, it becomes more important to be able to forecast

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such events. Music

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Music