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   AkaSci 🛰️ (akasci@fosstodon.org)'s status on Sunday, 07-Dec-2025 11:18:56 JST AkaSci 🛰️

   Two new active regions on the Sun's surface are now rotating into view.

   Region 4294 emitted an M5.9 (R2-Moderate) solar flare on Friday.

   Region 4299 emitted a 2x more energetic X1.9 (R3-Strong) solar flare today at 02:49 UTC. This could be part of region 4274 which emitted X class flares and CMEs 2-3 weeks ago.

   Solar weather experts will be keeping an eye on these regions as they rotate towards the center in about 6 days.

   https://www.swpc.noaa.gov/news/x19-flare-r3-strong-event
   Animation at https://www.star.nesdis.noaa.gov/goes/SUVI.php?sat=G19
   1/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Sunday, 07-Dec-2025 11:18:54 JST AkaSci 🛰️

     in reply to

     NOAA SWPC is predicting a higher than anticipated G3-level geo-mag storm this evening due to the arrival of a coronal hole high speed stream (CH HSS).

     This is unrelated to the recent X-class flares off the western edge of the Sun.

     Coronal holes are cooler, less dense regions than the surrounding plasma. Their open, magnetic field line structure allows the solar wind to escape more readily into space, resulting in streams of relatively fast solar wind.

     https://www.swpc.noaa.gov/
     4/n

     Steve's Place and Minoru Saba repeated this.
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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Sunday, 07-Dec-2025 11:18:54 JST AkaSci 🛰️

     in reply to

     The Sun's region 4299 produced an M8.1 (R2/Moderate) at 2039 UTC today. An hour earlier, it produced an M1.1 (R1/Minor) flare at 1921 UTC.

     This is the same region that rotated into view & produced an X1.9 flare on Dec 1 (an X1.9 flare is ~2.3x more energetic than an M8.1). It is now located just above the center of the Sun as seen from Earth. Any associated CME will be directed towards Earth. Geo-mag storms and auroras are likely on Dec 8-9.

     https://www.star.nesdis.noaa.gov/goes/SUVI.php?sat=G19
     https://www.swpc.noaa.gov/
     5/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Sunday, 07-Dec-2025 11:18:55 JST AkaSci 🛰️

     in reply to

     The NOAA Space Weather Prediction Center (SWPC) is forecasting a G2 (Moderate) geomagnetic storm during December 3 and 4.

     The coronal mass ejection (CME) associated with the X1.9 flare at 02:49 UT on December 1 from Region 4299 was aimed away from Earth but it is expected to deliver a glancing blow to our planet.

     More details and animation of the graphic at https://www.swpc.noaa.gov/
     3/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Sunday, 07-Dec-2025 11:18:56 JST AkaSci 🛰️

     in reply to

     Still from an animation from the NASA Solar Dynamics Observatory (SDO) of the X1.9 solar flare today.

     The GIF is at https://science.nasa.gov/blogs/solar-cycle-25/2025/12/01/strong-flare-erupts-from-sun-6/
     2/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Wednesday, 10-Dec-2025 07:06:10 JST AkaSci 🛰️

     in reply to

     The G3 geo-magnetic storm watch has now officially been cancelled. Forecast Kp index value for tonight is just 3 (G0).
     https://www.swpc.noaa.gov/products/alerts-watches-and-warnings
     https://www.swpc.noaa.gov/products/aurora-viewline-tonight-and-tomorrow-night-experimental
     11/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Wednesday, 10-Dec-2025 07:06:11 JST AkaSci 🛰️

     in reply to

     Chances are excellent for some good aurora viewing tonight in the upper- and mid-latitudes, esp. in the latter half of the night in Canada and northern U.S. states, due to the anticipated passage of the CME from 06 December.

     Keep those cameras ready!
     https://www.swpc.noaa.gov/
     9/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Wednesday, 10-Dec-2025 07:06:11 JST AkaSci 🛰️

     in reply to

     Looks like the anticipated CME either missed us or is running very late. The Geomagnetic Activity Kp index has been hovering around 1.0 over the past 9 hours. However, SWPC is still predicting a Kp index of 6.67 in the next few hours and good viewing tonight.
     🤞
     https://www.swpc.noaa.gov/communities/space-weather-enthusiasts-dashboard
     10/n

     Steve's Place repeated this.
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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Wednesday, 10-Dec-2025 07:06:12 JST AkaSci 🛰️

     in reply to

     The Sun's surface has been quite active overnight.

     Region 4298 emitted an X1.1 flare at 05:01 UTC, 1.3x stronger than the M8.1 flare from region 4299 on 06 Dec. Since region 4298 is towards the eastern edge of the Sun, any associated CME is unlikely to impact earth.

     Region 4299 has stayed active and there were two medium-strength flares at 00:10 and 6:54 UTC resp., not reported by SWPC yet.

     For GOES-19 SUVI time-lapse videos, see https://www.swpc.noaa.gov/products/goes-solar-ultraviolet-imager-suvi
     7/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Wednesday, 10-Dec-2025 07:06:12 JST AkaSci 🛰️

     in reply to

     Here is a link to a GOES-19 SUVI time-lapse video covering the past 11 hours. One can see eruptions of plasma that loop along the magnetic lines of force; some material falls back to the surface, other escapes into space.
     https://helioviewer.org/?movieId=210Y5
     8/n

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     AkaSci 🛰️ (akasci@fosstodon.org)'s status on Wednesday, 10-Dec-2025 07:06:13 JST AkaSci 🛰️

     in reply to

     The M8.1 solar flare that erupted from solar region 4299 at 2039 UTC on Saturday 06 December resulted in an earth-directed full-halo coronal mass ejection (CME).

     The CME is expected to impact Earth early to midday UTC on Tuesday 09 December, potentially causing periods of G3 (Strong) geomagnetic storming. There is a good possibility of auroras before sunrise in N. America.

     https://www.swpc.noaa.gov/
     6/n