On August 6, 2025, the sixth M-class solar flare, specifically an M1.1 flare of the penultimate power class, occurred on the Sun and lasted 10 minutes. This was reported by the Institute of Applied Geophysics (FGBU "IAG"). The event was recorded at 20:02 Moscow time in the X-ray range from sunspot group AR4167 (N09W89). The Solar Astronomy Laboratory of IKI RAS and ISZF SB RAS noted that within less than 24 hours, the Sun released energy equivalent to nearly an X-class flare, with the total number of C- and M-class flares reaching 18. Additionally, scientists warn of a powerful G2-level geomagnetic storm expected on August 8, triggered by a coronal mass ejection from the M4.4 flare on August 5.

Details of the M1.1 Flare

  • Classification: M1.1 (lowest level of M-class, moderate in power).
  • Time: August 6, 20:02 MSK, duration 10 minutes.
  • Active Region: AR4167, unlike the previous five August flares that occurred in AR4168.
  • Impact: Minor radio interference (R1 level) in high-frequency radio communication (3–30 MHz) on the Earth’s sunlit side. The coronal mass ejection (CME) is not Earth-directed, which lowers the likelihood of significant geomagnetic consequences from this flare.

Solar Activity in August 2025
August 2025 is marked by high solar activity during the peak of Solar Cycle 25. Major events include:

  • August 3: M2.9 flare (AR4168, 16:57 MSK, 11 minutes) — strongest in 1.5 months.
  • August 4: Two flares — M1.4 (08:15 MSK, 16 minutes) and M2.1 (07:57 MSK).
  • August 5: M4.4 flare (18:46–18:58 MSK), strongest in August at that point.
  • August 6: M1.1 flare (AR4167).
  • August 7: M2.2 flare (AR4168, morning, exact time unspecified).
  • Overall picture: In the first 6 days of August, 18 C- and M-class flares recorded, with total energy nearing X-class levels (highest level).

Solar flares are classified by the intensity of their X-ray radiation into classes A, B, C, M, and X, where A0.0 corresponds to 10 nW/m² in Earth orbit, with each subsequent class 10 times more powerful. M-class (10–100 μW/m²) causes moderate radio disruptions and, if associated with a CME, weak geomagnetic storms.

G2-Level Geomagnetic Storm on August 8
According to the Solar Astronomy Laboratory of IKI RAS and ISZF SB RAS, a G2-level (moderate, Kp=6) geomagnetic storm is expected on August 8, 2025, caused by the CME from the M4.4 flare on August 5. It will be the most powerful storm since June 13, 2025.

  • Cause: The high-speed core of the CME from the M4.4 flare is expected to reach Earth around 07:00 MSK on August 8. Additionally, geomagnetic disturbances are possible overnight due to the influence of a coronal hole.
  • Consequences:
    • Weather-sensitive people: Possible headaches, blood pressure spikes, insomnia, fatigue. It is recommended to reduce physical activity, monitor blood pressure, and maintain a healthy routine.
    • Technology: Potential disruptions in GPS navigation, aviation communication, satellite operations. Communication and aviation operators are advised to use backup channels.
    • Auroras: Enhanced auroras in high latitudes (Northern Europe, Canada, northern Russia).
  • Forecast: Long-term forecasts are imprecise, but current models indicate moderate impact. Additional disturbances may occur on August 9, 19, 20, and 28–30.

Context of Solar Cycle 25
The Sun is currently at the peak of the 25th solar cycle (2024–2026), showing record activity: over 50 X-class flares recorded in 2024, and already 9 in 2025, including X8.7 (May 14) and X6.3 (February 23). The August events confirm continued high activity, although the M1.1 flare itself does not pose a major threat.

In Conclusion
The M1.1 flare recorded on August 6, 2025, in region AR4167 adds to an already intense August, previously dominated by region AR4168. The cumulative energy of the flares approaches the X-class threshold, highlighting a tense phase of the solar cycle. The G2-level geomagnetic storm expected on August 8 will be the most significant geomagnetic event in two months. Weather-sensitive individuals should prepare for possible discomfort, and tech operators for potential disruptions. Stay tuned for updates from IKI RAS and NOAA for accurate forecasts.