The K7RA Solar Update

The average daily sunspot numbers dropped this week, from 83.1 to 56, while the average daily solar flux declined from 118.9 to 101.4. Sunspot numbers for September 13-19 were 44, 44, 53, 77, 51, 61 and 62, with a mean of 56. The 10.7 cm flux was 99.1, 100.5, 97.5, 97.3, 101.5, 104.3 and 109.8, with a mean of 101.4. The estimated planetary A indices were 6, 5, 6, 7, 6, 8 and 14, with a mean of …

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