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Astronomy

The Solar Wind and Its Interaction with Planetary Magnetospheres

Quick fact

Earth's magnetosphere deflects about 99% of the solar wind's particles, but the remaining 1% that leaks in creates the auroras and powers the Van Allen radiation belts.

Why this is interesting

You've seen shimmering curtains of light in the night sky—auroras—but did you know they're caused by a cosmic wind blowing from the Sun? What happens when that wind hits Earth's invisible magnetic shield?