The sun belted out the most powerful type of solar flare Monday night, known as an X-class flare (the weaker flare classes are M-class, medium-sized, and C-class, small-sized). It was the latest in a flurry of 4 flares hurled out by the sun since the weekend.
Fortunately, the X-class flare was not directed at Earth. But space weather forecasters caution the very active sunspot region - known as AR1598 - responsible for these flares is slowly rotating towards Earth in the coming days.
“[T]he potential for continued activity remains so stay tuned for updates as Region 1598 makes its way across the visible disk,” writes NOAA’s Space Weather Prediction Center.
Monday night’s flare, rated X1.8, was the 15th X-class flare emitted during the current solar cycle, which began February 15, 2011.
The number associated with the flare class indicates strength. An X3 flare is three times as strong as an X1 flare.
“The largest X-class flare in this cycle was an X6.9 on Aug. 9, 2011,” NASA writes. “This is the 7th X-class flare in 2012 with the largest being an X5.4 flare on March 7.”
No earth-bound coronal mass ejection (CME), or burst of plasma - was associated with Monday night’s flare. Earth-directed CMEs can produce aurora ( northern lights) and geomagnetic storms capable of disrupting satellite communications and the electrical grid.
The flare did produce a short-lived high-frequency radio blackout.