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Thanks, Jennifer.

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Aurora tell us in a dramatic way that something invisible is happening above our heads in space to light up our skies.

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We can use sophisticated Earth-orbiting satellites to learn more about the causes of the aurora.

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The Imager for Magnetosphere-to-Aurora Global Exploration, or IMAGE,

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is a NASA satellite that lets us see the invisible activity that swirls around the Earth

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and eventually causes aurora to appear.

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When a solar storm collides with Earth, one of the first signs of the disturbance

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is a collection of particles called the ring current.

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It's an invisible river of charged particles extending over 30,000 kilometers from Earth.

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Much of the matter in this current actually comes from the Earth's upper atmosphere

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in gigantic plumes and fountains of gas from the polar regions.

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But we still don't know how the particles get their energy.

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Another part of the upper atmosphere, seen by IMAGE for the first time,

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is what scientists call the plasmasphere.

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It extends out into space at least 10,000 kilometers.

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You should think of it as the outer limits to the ionosphere.

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During severe storms, parts of the plasmasphere are stripped off,

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but then reform as new gas flows out of the Earth's upper reaches.

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And, of course, IMAGE also provides scientists with movie-like, high-resolution views of the aurora seen from space.

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Over the South Pole, the satellite dips down to 1,000 kilometers

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to show us never-before-seen details in auroral structure.

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The aurora in the South Pole is called Aurora Australis.

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Over the North Pole, we see a more distant view and a bigger picture.

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We can relate this big picture with views of the ring current and plasmasphere

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to track the evolution of an aurora from cradle to grave.

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The reason why we're so keen to understand the aurora

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is that the aurora are kind of like a final examination.

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If we can really understand how they work,

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that means we also understand all the other things about Earth's environment as well.

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We have billions of dollars of satellite technology in space,

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astronauts living and working in space,

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and on the ground, many kinds of systems that are affected by solar storms.

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An electrical blackout in Canada back in 1989 cost billions of dollars.

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We have lost over $2 billion of expensive communication and research satellites

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in the last 10 years alone.

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Solar storms have tremendous potential to cause damage to us.

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Only by understanding aurora and the events that lead up to them

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can we improve our ability to predict how to avoid the harmful effects of space weather storms.

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The real challenge is to get enough early warning that a storm is approaching.

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That's why it's also important to look at the sun for clues to the next storm.

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Thanks, Sten.

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Okay, guys, now it's your turn to apply data analysis and measurement skills

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with this really cool activity.

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Sten, they are gorgeous, aren't they?

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Aren't they amazing?