The K7RA Solar Update

The average daily sunspot numbers rose this week from 56 to 81.3, while the average daily solar flux increased from 101.4 to 129.7. Sunspot numbers for September 20-26 were 68, 74, 46, 57, 90, 121 and 113, with a mean of 81.3. The 10.7 cm flux was 117.4, 116.9, 124.5, 133.6, 136.6, 139.8 and 139.2, with a mean of 129.7. The estimated planetary A indices were 9, 5, 4, 2, 2, 2 and 6, with a mean …

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