When it comes to extreme weather, it's safe to say a "space hurricane" qualifies.
Scientists said last week they observed a previously unknown phenomenon — a 620-mile-wide swirling mass of plasma that roiled for hours in Earth's upper atmosphere, raining electrons instead of water.
The researchers labeled the disturbance a space hurricane because it resembled and behaved like the rotating storm systems that routinely batter coastlines around the world. But until now, they were not known to exist.
"It really wasn't expected," said Larry Lyons, a professor of atmospheric and oceanic sciences at the University of California, Los Angeles. "It wasn't even theoretically known."
