The largest sunspot region of Solar Cycle 24 - Region 2192 ('beta-gamma-delta') unleashed its fourth X-class solar flare since it rotated onto the Earth side of the Sun on October 25, 2014. The event lasted more than 1 hour. It started at 16:55, peaked at 17:08 as X1.0 and ended at 18:11 UTC.
Although this region is continuously producing strong and major flares it still didn't deliver a significant Coronal Mass Ejection (CME). Analysis of the latest event is still in progress but it too appears without a significant CME.
Radio Blackout threshold reached R3 (Strong) level that can cause wide area blackout of HF radio communication, loss of radio contact for about an hour on sunlit side of Earth and low-frequency navigation signals degraded for about an hour. The main communications impacts from this event are over the Pacific Ocean.
The region still has a potential to unleash powerful Earth directed eruptions, however, as it rotates away from the center of the disk, and judging by its activity so far, chances we'll see them reaching Earth are decreasing.
Yesterday's X3.1, the sixth strongest solar flare of the current cycle, did produce a narrow CME which was observed in SOHO LASCO C2 imagery beginning at 25/21:48 UTC but it was directed well south of the Sun-Earth line.
Forecasters estimate 85% chance for M-class and 45% chance for X-class solar flares over the next two days (October 25 - 27).
Space Weather Message Code: SUMX01
Serial Number: 107
Issue Time: 2014 Oct 25 1825 UTC
SUMMARY: X-ray Event exceeded X1
Begin Time: 2014 Oct 25 1655 UTC
Maximum Time: 2014 Oct 25 1708 UTC
End Time: 2014 Oct 25 1811 UTC
X-ray Class: X1.0
Optical Class: 3b
NOAA Scale: R3 - Strong
NOAA Space Weather Scale descriptions can be found at
Potential Impacts: Area of impact consists of large portions of the sunlit side of Earth, strongest at the sub-solar point.
Radio - Wide area blackout of HF (high frequency) radio communication for about an hour.
There are currently 7 numbered sunspot regions on the Earth side of the Sun.
Region 2192 exhibited penumbral growth in its leader spot area with umbral consolidation in its trailer spot area, and persists as the most threatening region on the visible disk. Minor growth was observed in the trailer spot area of Region 2195 (N08E40, Dso/beta) and the other regions on the disk are either stable or in decay.
Sunspots on October 25, 2014. Image credit: NASA SDO / HMI
2187 - Alpha
2192 - Beta-Gamma-Delta
2193 - Beta
2194 - Beta
2195 - Beta
2196 - Alpha
2197 - Alpha
Featured image: NASA SDO / AIA 131 - October 25, 2014 at 17:08 UTC.