PROTONS ARE RAINING DOWN ON EARTH:

[Charles Bresnahan]

Yesterday's long-duration solar flare from sunspot 4492 accelerated a stream of energetic protons toward Earth. They are striking our atmosphere now. This is called a "solar radiation storm." Current storm levels are minor (S1-class), which means the protons pose no significant threat to astronauts or air travelers. However, the storm is causing a shortwave radio blackout inside the Arctic Circle.