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Astronomy

What Causes the Aurora Borealis and Australis?

Quick fact

The particles that create auroras travel 150 million kilometers from the Sun at speeds up to 72 million km/h, yet only a tiny fraction ever reach our atmosphere—and Earth's magnetic shield guides them toward the poles.

Why this is interesting

Have you ever seen a shimmering curtain of green light dancing across the Arctic sky and wondered what sorcery creates such a breathtaking display?