Cylindrical magnetic passageways about the width of Earth, depicted here with a measuring satellite in the foreground, open and close between Earth and the Sun every eight minutes. They allow tons of high-energy particles to flow one-way across ninety-three million miles as they form above the equator and then roll over the poles.
Satellites have flown through them, measured their dimensions and sensed the particles flowing past. Now scientists are studying the portals to see how they work and what they do. Among the unanswered questions: why do they form every eight minutes? Here’s betting they affect our climate a lot more than carbon dioxide does.















