Solar activity continues to increase, but is still occurring at a safe distance from Earth.
The Sun continues to exhibit two large centers of activity on the side visible from Earth, both of which are returning to the planet repeatedly. These groups previously crossed the solar disk in mid-October, after which, due to the Sun's rotation, they passed beyond the right (western) horizon and have now reappeared on the eastern horizon, proving that the Sun, like the Earth, is round (we are sure there will be objections). The upper of the two groups was the most active during the previous passage and, in fact, single-handedly generated a nearly tenfold increase in flare activity. This same group, apparently, subsequently produced several level X flares on the far side. Currently, the main activity is also observed in this group. In catalogs, for unclear reasons, this active center was divided into two groups: 4272 (front spots) and 4274 (distant spots). The flares in the catalog are currently attributed primarily to the distant group (4274). The lower group received the number 4275 yesterday.
Over the past 24 hours, five strong M-level flares were recorded on the Sun. The strongest event, M5.0 (50% of the highest M-level), occurred midday, around 1:00 PM Moscow time. The flare activity index during this period rose from around 4 to over 7 on a 10-point scale. During their last solar disk transit, these regions reached a level of 8 out of 10, although they visually had less energy back then. Therefore, this is likely not the limit, and activity will increase. Both regions are clearly more prone to producing isolated strong flares than wasting energy on many smaller events. For this reason, the probability of M-level flares is quite high, including today.
Plasma emissions from the flare centers are currently passing by Earth. The upper region is currently approximately 60 degrees from the direction of Earth, which is considered safe. But by this time tomorrow, this angle will have shrunk to 45 degrees, and the ejecta could begin to brush the Earth's edges. By the weekend, both active centers will essentially be aligned with the Sun and Earth.
The most interesting aspect is the "silence" of the lower active center, which is larger and potentially more dangerous. It's worth noting that it was just as silent during its last passage. I don't want to think it's stubbornly storing up energy for a single super-explosion for three weeks now. But, as the saying goes, still waters run deep...
Laboratory of Solar Astronomy,SRI RAS
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