On Thursday, September 12, the Sun experienced an X1.3 class flare, one of the highest categories. Now heavy particles are flying away from it towards the Earth. It is expected that spectacular auroras may decorate the sky this weekend.
X-class solar flares
On Thursday, September 12, a region of a still unnumbered sunspot made its presence known with an X1.3-class flare. Such events are the most powerful of their kind and are usually accompanied by a full or partial loss of high frequency (HF) radio signals for sunlit locations on our planet.
The powerful flare, which peaked at 9:43 a.m. UTC, affected communication bands in Africa, Europe and parts of Asia. However, this is not the end, because heavy and slow particles have not reached us yet.
Forecasters at NOAA’s Space Weather Prediction Center will continue to analyze the data to figure out what happens when Earth’s magnetic field is reached by particles from both this flare and a group of M-class flares (the second strongest in the class) that also occurred Thursday morning near two other sunspots, AR 3811 and AR 3814.
The National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center (SWPC) also reported that the geomagnetic storm occurred Thursday morning (Sept. 12) at 5:46 p.m. ET (02:46 p.m. UTC) at a G3 (moderate) level. This is level three on a five-point scale.
Coronal mass ejections and geomagnetic storms
The storm resulted from a coronal mass ejection (or CME), an explosion of solar plasma and magnetic field that accompanied the flare that occurred earlier this week, on September 10. At that time, the Sun had already risen over the eastern half of the United States, but in some places in the west, the auroras produced by the flare could be seen.
When a sunspot region emits a solar flare, the CME is pushed away from its corona. When they are directed toward the Earth, we feel their effects a few days later.
In fact, aurora hunters will have another opportunity on Friday (September 13) when another geomagnetic storm is expected, caused by the CME that began its path from the Sun on Tuesday, September 10 in the morning.
According to www.space.com