Federal forecasters say a brief but strong solar flare Wednesday morning temporarily blacked out a few radio communication systems before weakening.
Space Weather Prediction Center forecaster Christopher Balch said it affected radio that uses part of the upper atmosphere. That includes some radar and plane systems, but not all, and amateur radio.
The storm came from a large group of sunspots and hit Earth between 10 a.m. and 11 a.m. EDT. Balch said the storm briefly was rated as strong for affecting Earth radio systems but then dropped to minor levels.
He said so far forecasters see no high-energy particles coming from the flare. That means other effects are not expected, such as changes in the colorful northern lights, or harm to the electrical grid or satellites.The solar flare actually erupted on Sunday, so 2 to 3 days for the solar storm to reach Earth. The Washington Post has more information on the sunspot that was the source of the flare:
The sunspot region, known as AR2192, is so big that it is visible to a (well-protected) naked eye. ...
“This is the largest sunspot group since November of 1990,” said Doug Biesecker, a researcher at the National Weather Service Space Weather Prediction Center. Its size is 2,740 millionths of the solar disc which, according to the Web site The Sun Today, is roughly the size of Jupiter.
NASA says the largest sunspot on record, observed in 1947, was almost three times as large as AR2192. Consider that AR2192 is 80,000 miles in diameter – and you could lay 10 Earths across it.