It is not yet known whether the flare was accompanied by a coronal mass ejection (CME) - an outburst of particles that can trigger a geomagnetic storm on Earth and damage the electrical grid.

Joe Kunches of NOAA’s Space Weather Prediction Center in Boulder said one of the NASA satellites tasked with watching for solar weather, SOHO, was “on maneuvers” when the flare launched.

That will make the task of predicting the course of any subsequent CME more difficult.

“The home plate umpire wasn’t paying any attention,” said Kunches.

[link to www.washingtonpost.com]