The Sun’s surface is about 5,500°C (9,900°F), but its outer atmosphere—the corona—blazes at over a million degrees. That seems counterintuitive. Normally, things get cooler as you move away from a heat source, but the Sun does the opposite. Scientists think the answer lies in magnetic fields snapping and reconnecting, releasing bursts of energy that superheat the corona. It’s like a campfire where the air above the flames is hotter than the fire itself—a mystery we’re still trying to solve.
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