On September 11 and 12 two powerful CMEs hit Earth, producing a G3 class geomagnetic storm. The result was a planetary A index of 44 on Friday, and during the final three hours of the UTC day (2:00 PM to 5:00 PM PDT) the planetary K index reached 7, which is very high.
Overall solar activity is down, with the average daily sunspot number declining from 152 to 124.9 in the latest reporting period…
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