A major solar flare registered as X2.0 erupted from Active Region 3878 at 21:20 UTC on October 31, 2024. The event started at 21:12 and ended at 21:27 UTC. The flare was immediately followed by a long-duration M9.5 flare. Meanwhile, the solar radiation storm that started on October 26 entered the 7th day and continues at S1 – Minor levels.
There were no radio signatures that would suggest a coronal mass ejection (CME) was produced during X2.0 solar flare on October 31.
The event was associated with 10cm Radio Burst (tenflare) lasting 14 minutes and with a peak flux of 910 sfu. This indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. It can indicate significant radio noise associated with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.
Radio signatures were forecast to be most degraded over the Pacific Ocean at the time of the flare.
While CME was probably not produced by this event, Region 3878 has a ‘beta-gamma-delta’ magnetic configuration and is capable of producing more strong to major solar flares. It’s moving toward the center of the disk which means Earth-directed CMEs from this region are possible in the days ahead.
This is the 9th X-class solar flare during the month of October.
Solar Cycle 25, which began in December 2019, has reached its maximum phase, known as solar maximum.
This period is characterized by heightened solar activity, including increased sunspot numbers and solar flares. The duration of solar maximum varies, typically lasting between several months to a few years.
Current projections suggest that Solar Cycle 25’s maximum phase will continue into 2025.
A total of 7 M-class flares were observed from Regions 3875, 3876, and 3878 on October 31. Growth was observed in Regions 3875 and 3876 while the remaining regions were either stable or in decay.
Analysis of a CME associated with an M2.4 solar flare from Region 3877 at 12:52 UTC resulted in a possible glancing blow on November 3.
Solar radiation storm that started at around 16:35 UTC on October 26 and reached S2 – Moderate levels at 09:15 UTC on October 27 continues at S1 – Minor levels. This is now 7th day in a row we are experiencing enhanced solar radiation levels — elevated levels of energetic particles, particularly protons, around Earth.
There are minimal biological impacts for individuals at ground level or those flying at regular altitudes at S1 level.
Passengers on high-altitude flights near the polar regions may experience a slight uptick in radiation exposure, although it remains within safe limits for occasional flyers and does not pose a significant health risk.
For satellite operations, an S1 storm generally introduces minimal disturbances. Satellites in low Earth orbit might experience a minor degradation in performance due to increased background noise in imaging instruments, but this is usually manageable. Operators may make minor adjustments to counteract these conditions, ensuring that the effect on data quality and satellite function remains negligible.
High-frequency (HF) radio communications might encounter slight interference at high latitudes due to increased absorption in HF radio bands.
Satellite navigation systems, such as GPS, may experience a minor reduction in accuracy at high latitudes, particularly for precision-based navigation efforts.
Enhanced solar wind conditions were observed on October 31, with an increase in the interplanetary magnetic field detected later in the day. Total field strength reached 9 nT, while the Bz component decreased to -8 nT. Solar wind speeds ranged from 450 to 600 km/s, with the phi angle predominantly in the negative sector.
Nominal solar wind conditions are anticipated on November 1, followed by mildly enhanced parameters on November 2 due to positive polarity coronal hole high-speed stream (CH HSS) influences.
Weakly enhanced conditions are forecasted for November 3, influenced by continued but diminishing CH HSS effects, alongside a potential glancing blow from the October 31 CME.
The geomagnetic field is expected to be mostly quiet on November 1. Quiet to active levels are likely on November 2 due to positive polarity CH HSS influences. Quiet to active conditions are anticipated on November 3, with CH HSS effects gradually diminishing and a possible CME impact from October 31.
References:
1 Forecast discussions – NOAA/SWPC – Issued at 12:30 UTC on October 31 and 00:30 UTC on November 1, 2024