A G2-class magnetic storm is expected to reach Earth on October 11. The warning was issued by the Space Weather Prediction Center of the US National Oceanic and Atmospheric Administration (NOAA) after two coronal mass ejections were tracked from the Sun.
“A G2 geomagnetic storm watch has been issued for October 11“, NOAA said. According to the institution, the October 8th eruption was faster than the one recorded a day earlier, and the two plasma structures are expected to merge on their way to Earth.
Initial calculations predicted a weak G1 class storm on October 11. NOAA's updated forecast is now for G2, which means a moderate geomagnetic storm.
The expected phenomenon is related to coronal mass ejections, which are clouds of magnetized plasma ejected from the Sun. When they reach the Earth's magnetic field, temporary interference in radio communications, navigation systems and the operation of satellites is possible.
On October 8, active region 4549 produced an eruption of class M6.7. It reached its maximum strength at 15:48 UTC. The event was accompanied by a coronal mass ejection, which is considered one of the causes of the expected geomagnetic activity over the weekend.
The eruption also caused radio interference of level R2 on the illuminated side of the Earth. This class means a moderate impact on high-frequency radio communications, including a possible short-term loss of radio communication.
The forecast for October 11 remains dependent on the exact speed and direction of the two plasma clouds. The stronger impact could occur when they merge and in a favorable orientation of the magnetic field for a geomagnetic storm.