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Astronomy

How Solar Flares Impact Earth's Ionosphere and Radio Communications

Quick fact

A single X-class solar flare can cause a planet-wide radio blackout on the sunlit side of Earth within minutes, affecting high-frequency (HF) radio communications used by aircraft, ships, and emergency services.

Why this is interesting

Imagine your radio suddenly goes silent, and you can't hear the emergency broadcast. That's what happens when a solar flare rips through Earth's upper atmosphere—even though the flare is 150 million kilometers away.