Sun news: Auroras last night, and more to come!

Sun news September 2: Auroras last night, and more to come!

(11 UTC to 11 UTC)

Today’s top story: A coronal mass ejection (CME) that erupted from the sun on Saturday slammed into Earth’s magnetic field late last night, triggering a G2 (moderate) geomagnetic storm. And forecasters expect geomagnetic activity to intensify tonight, with potential G3 (strong) storms and even a slight chance of G4 (severe) conditions. Sky watchers at high latitudes, stay alert! Auroras could be widespread if skies are dark and clear, although the bright waxing gibbous moon may interfere with viewing.

• Flare activity: Solar activity remained low with only C-class flares. A total of 13 C flares were fired in the past day.
  • The strongest was a C3.9 from AR4196 (S11W36) at 19:14 UTC Sep 1.
  • Other notable events: C3.1 (AR4201 at 17:43 UTC on September 1), C3.0 (AR4207 at 18:12 UTC on September 1), C3.0 (AR4207 at 11:51 UTC on September 1), C2.8 (AR4199 at 00:49 UTC on September 2).
  • Flaring regions: AR4207 produced four C flares, AR4196 produced three, AR4197 produced two, and we saw additional activity from AR4201, AR4191, and AR4199.
• Sunspot regions: Ten active regions currently dot the solar disk.
  • AR4197 (southwest, beta-gamma) produced the two strongest flares of the period and remains the most flare-capable region.
  • AR4199 (northwest, beta) gained sunspots but produced only small C-class events.
  • AR4207 (northeast limb, beta) rotated into view with trailing spots visible and produced several C-class flares.
  • AR4191 (northwest, beta) was stable, with a few small C flares.
  • Other regions remained quiet, with little magnetic complexity.
• Blasts from the sun? The coronal mass ejection (CME) from August 30 reached Earth around 21:00 UTC Sep 1, producing the ongoing geomagnetic storm. No new Earth-directed CMEs were observed in coronagraph imagery.
• Solar wind: The solar wind jumped sharply with the CME impact, climbing from ~400 km/s to peaks of 600–675 km/s. The total interplanetary magnetic field (Bt) reached moderate levels, with the Bz mostly northward but occasionally dipping southward. Conditions remain strongly enhanced.
• Earth’s magnetic field: Earth’s magnetic field reached G2 (moderate) storm conditions. Forecasts call for possible G3 (strong) levels during the first half of Sep 2, before easing to G1–G2 (minor to moderate) later in the day. Activity should drop back to unsettled to active on Sep 3, and quiet with isolated unsettled periods by Sep 4.

What’s ahead? Sun-Earth forecast

• Flare activity forecast: M flares remain likely (R1–R2, minor to moderate), with AR4197 the primary source. A slight chance exists for an X-class (R3, strong) flare through Sep 4.
• Geomagnetic activity forecast:
  • Sep 2: G2–G3 storms likely, with a slight chance of reaching G4. High-latitude auroras possible if skies are dark and clear.
  • Sep 3: G1–G2 activity possible early, trending toward unsettled-to-active conditions as CME effects wane.
  • Sep 4: Mostly quiet with isolated unsettled periods.
• Radiation forecast: High-energy particle levels rose ahead of the CME arrival but remain below the S1 threshold. A slight chance remains that levels could cross the S1 line early on Sep 2 with secondary shock effects. Any major flare from AR4197 could also boost particle counts.

Sun news September 1: Auroras incoming! Severe storming possible tonight

(11:00 UTC Aug 31 – 11:00 UTC Sep 1)

The impressive full-halo coronal mass ejection (CME) that was blasted from the sun on Saturday is expected to impact Earth’s magnetic field later today. This huge burst of sun-stuff could trigger G2–G3 (moderate-strong) geomagnetic storming, with a chance of G4 (severe) storms depending on the CME’s magnetic orientation. That means it could be a brilliant night to see auroras! Clear skies, everyone.

• Flare activity: Solar activity decreased to low levels, with only C-class (common) flares recorded over the past day. Highlights include:
  • C6.8 — AR4202 (S15E01) at 18:26 UTC on Aug 31.
  • C4.9 — AR4197 (S20W29) at 03:25 UTC on Sep 1.
  • Multiple smaller C flares from AR4197 (beta–gamma, now losing its delta complexity) and AR4207 (emerging in the northeast limb region).
• Sunspot regions: Ten numbered regions are on the Earth-facing disk.
  • AR4197 (S18W24): Still the largest and most complex sunspot region, but now showing minor decay and loss of delta spots. This region continues to produce frequent C flares.
  • AR4202 (S15E01): Produced the largest flare of the period (C6.8).
  • AR4207 (N30E58): Developing additional trailing sunspots, but its proximity to the horizon makes classification tricky.
  • AR4208 (N18W68): Newly numbered, simple beta region.
  • AR4191 (N11W68): Beta configuration, stable with minor C-class flares.
• Blasts from the sun? The full-halo coronal mass ejection (CME) tied to the M2.8 flare on August 30 remains Earth-directed. Arrival is expected late Sep 1 into Sep 2. No new Earth-directed CMEs were detected during the past 24 hours.
• Solar wind: Solar wind remained normal, rising from ~375 km/s to ~500 km/s late on Aug 31 under weak coronal hole influence. The interplanetary magnetic field (IMF) peaked at normal levels, and the Bz varied between northward and southward. Forecasters expect mildly enhanced conditions early Sep 1, then a significant boost late Sep 1–Sep 2 as the CME arrives.
• Earth’s magnetic field: Conditions stayed quiet (Kp 1–2), with one unsettled period between 9 and 12 UTC yesterday. Storm levels should rise late today into tomorrow, likely reaching G2–G3, with a chance of G4 conditions.
• Energetic particles: The level of energetic particles remains slightly elevated, but below the S1 (minor) radiation storm threshold. A minor storm remains possible through September 3 if additional eruptive flares occur.

Sun news August 31: M flares erupt, sun stuff on the way

(11:00 UTC Aug 30 – 11:00 UTC Aug 31)

After a steady drumbeat of C flares the day before, the sun ramped up with three M-class solar flares during the last 24 hours. The strongest was a long-duration M2.8 at 20:02 UTC on August 30 from AR4204 (north-central disk). It launched a full-halo coronal mass ejection (CME) now under analysis. Early signs suggest it is likely Earth-directed, with an expected arrival window of September 1–2. Complex region AR4197 (now beta–gamma–delta) produced the other two M flares and remains the most flare-productive area. Newcomer AR4207 has rotated onto the northeast limb and may evolve as it moves further into view.

• Flare activity: Activity increased to moderate, with:
  • M2.8 — AR4204 (N04E12) — peaked 20:02 UTC on August 30, long-duration and CME-associated.
  • M1.3 — AR4197 (S19W08) — peaked 14:09 UTC on August 30.
  • M1.2 — AR4197 (S18W06) — peaked 15:59 UTC on August 30.
  • Several C flares (strongest C7.2 from AR4196 at 22:23 UTC on August 30).
• Sunspot regions: Eleven numbered regions on the Earth-facing disk.
  • AR4197 (S18W10): beta–gamma–delta; multiple M flares and continued complexity.
  • AR4204 (N04E12): Likely beta; source of the long-duration M2.8 and associated CME.
  • AR4207 (N30E69): New on the northeast limb (alpha for now); reclassification likely as it rotates in.
  • AR4191 (N10W55): beta; largely stable.
• Blasts from the Sun? An asymmetric full-halo CME was detected around 20:30 UTC on Aug 30, most likely tied to the M2.8 event. Initial analysis indicates this CME is probably Earth-directed; modeling is in progress.
• Solar wind: Nominal background conditions with speeds ~350–425 km/s (780,000-950,000 mph). Total field (Bt) peaked near 10 nT (nominal); the interplanetary magnetic field (IMF) north–south component (Bz) ranged between about +8 and -6 nT (nominal).
• Earth’s magnetic field: Quiet over the past day (Kp 1–2 ).

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Bottom line: Sun news September 2, 2025. The arrival of a blast of sun-stuff brought auroras last night, and even stronger geomagnetic storms are possible tonight.