Laboratory forecasts solar plasma impact on Earth on Sunday

Two solar plasma clouds ejected on October 7 and 8 may merge and reach Earth around midday on October 11. The Russian Academy of Sciences solar astronomy laboratory published the forecast on October 9.

The laboratory is tracking three clouds. The first followed an M1.4 flare on October 6. Its daytime forecast anticipated arrival after 18:00 Moscow time on October 9, potentially producing a G2 geomagnetic storm and auroras at latitudes of 55–60 degrees and farther north.

Late that evening, however, the laboratory website showed quiet geomagnetic conditions, with a maximum Kp index of 4 over the previous 24 hours. The daytime expectation should therefore not be treated as confirmation that a storm had begun.

The laboratory provisionally forecasts a second G2 storm on Sunday following the proposed merger of the later ejections. Scientists also see a possible subsequent decline in solar activity if the new sunspot groups lack resources for further growth. Cloud arrival times and impact strength remain model-based estimates.