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What Causes the Northern Lights to Dance Across the Sky?
是什么让北极光在夜空中舞动？
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The Northern Lights, or auroras, happen when charged particles from the Sun hit Earth’s upper atmosphere.
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These solar winds travel along magnetic field lines and concentrate near the North and South Poles.
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When particles strike oxygen and nitrogen atoms, they excite electrons, which then emit light as they calm down.
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Green light comes from oxygen at lower altitudes, while red and purple appear higher up or during strong storms.
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Magnetic reconnection—sudden shifts in Earth’s magnetic field—makes the lights flicker and swirl rapidly.
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Auroras follow an 11-year solar cycle, growing brighter and more frequent near solar maximum.
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Cameras capture movements too fast for our eyes, revealing waves, curls, and even 'auroral flames'.
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Scientists use satellites and ground stations to predict aurora visibility days in advance.
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This cosmic light show links our planet directly to the Sun’s explosive energy output.
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Watching the aurora reminds us that space weather shapes what we see—even from our own backyard.