Only five new sunspot groups emerged this week. First was on
November 7, next on November 9, two more on November 11, and another
on November 13.
Average daily sunspot number declined from 193.4 to 141.6, while
average daily solar flux went from 248.4 to 203.7.
Predicted solar flux is 145 on November 15-16, 155 on November
17-18, then 145 on November 19, 140 November 20-21, then 235, 240,
255 and 260 on November 22-25, 270 on November 26-27, then 255 and
250 on November 28-29, 240 on November 30 and December 1, 230 on
December 2-3, and 225 and 220 on December 4-5, then 225 on December 6-7, and 175, 170, and 175 on December 8-10, then 165 on December 11-14, 178 and 185 on December 15-16, 200 on December 17-18, then 235, 240, 255 and 260 on December 19-22.
Estimated planetary A index is 12, 10, 8, 12 and 8 on November
15-19, 5 on November 20-24, 10 on November 25-26, then 8, 5, 5 and
10 on November 27-30, then 12, 9, 8, 7 and 5 on December 1-5, 12 on
December 6-8, then 8, 12 and 10 on December 9-11, 8 on December
12-13, then 5, 8, 5 and 12 on December 14-17.
From HMI Science Nuggets, a possible explanation for solar cycle
double peaks:
Weekly Commentary on the Sun, the Magnetosphere, and the Earth’s
Ionosphere – November 14, 2024, from F.K. Janda, OK1HH:
“Of the three active regions in the past few days, two have fallen
behind the western limb of the solar disk. Therefore, the solar flux
has dropped significantly. The third sunspot group was AR3889, which
crossed the central meridian midweek. Its size of over 400
millionths of the solar disk area, and in particular the optical ‘F’
and magnetic ‘Beta-Gamma-Delta’ configurations, indicate that the
production of moderate size flares will continue. So, because it is
in the west, like most coronal holes, the solar wind should
intensify, and the Earth’s magnetic field activity should increase.
“This development, in fact, has already begun on November 14. First,
conditions worsened after the polarity of the longitudinal component
of the interplanetary magnetic field changed to negative between
0200-0500 UTC, while the density of protons in the solar wind
increased. This was correctly followed by an increase in its
velocity from 350 km/s to 440 km/s. Due to the anticipated increase
in the solar wind, a further several days of turbulence is expected,
followed by calming down only during the following week.”
The latest report from Dr. Tamitha Skov, WX6SWW:
Send your tips, reports, observations, questions and comments to
k7ra@arrl.net. When reporting observations, don’t forget to tell us
which mode you were operating.
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Also, check this article:
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“Understanding Solar Indices” from September 2002 QST.
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Sunspot numbers for November 7 through 13, 2024 were 164, 167, 176,
121, 138, 116, and 109, with a mean of 141.6. 10.7 cm flux was
239.2, 231, 220.9, 230.6, 182.2, 171.7, and 150.3, with a mean of
203.7. Estimated planetary A indices were 9, 11, 32, 25, 10, 5, and
7, with a mean of 14.1. Middle latitude A Index was 7, 7, 24, 15, 7,
4, and 5, with a mean of 9.9.