At 2330 UTC on July 24, Australia’s IPS Radio and Space services issued a geomagnetic disturbance warning. Increased geomagnetic activity is expected due to a coronal mass ejection. They predict quiet to unsettled conditions on July 25, active to minor storm on July 26, and active conditions on July 27.
As this bulletin nears release early Friday morning, the planetary A index was 4 on four rece…
American Radio Relay League | Ham Radio Association and Resources
Solar activity was down this week, with the average daily sunspot number at 49.6, less than half last week’s figure. The average daily solar flux dropped 22 points to 97, and geomagnetic activity was quiet also. Sunspot numbers for March 21-27 were 60, 54, 56, 45, 56, 41 and 35, with a mean of 49.6. The 10.7 centimeter flux was 106.1, 100.9, 98.2, 96, 92.6, 92.4 and 93, with a mean of 97. The e…
American Radio Relay League | Ham Radio Association and Resources
This past week, there was a decline in the solar and geomagnetic indices: The average daily sunspot number dropped nearly 21 points to 57.7, while the average daily solar flux softened by 4.7 points to 100.9 and the average daily planetary A index declined 6.4 points to 5.1. This isn’t much of a change, but geomagnetic activity was low already, and this is even lower.
Sunspot numbers for Februar…
American Radio Relay League | Ham Radio Association and Resources
Solar activity rose moderately this week, with the average daily sunspot numbers up nearly 3 points to 120.9, and the average daily solar flux rising more than 28 points to 166.8. There was quite a bit of geomagnetic activity — the most happening on July 9 — when the mid-latitude A index reached 29, the planetary A index was 30 and Alaska’s college A index was 60. Sunspot numbers for July 5-1…
American Radio Relay League | Ham Radio Association and Resources