|GOES Solar X-Ray Image / Courtesy |
NOAA Space Weather Prediction Center
The largest solar radiation storm since 2005 has struck the Earth, touching off radio blackouts, geomagnetic storms and aurora displays in upper latitudes. According to CQ Propagation Editor Tomas Hood, NW7US, a long-duration magnitude M8.7 (M9-class) X-ray flare erupted in NOAA Active Sunspot Region (AR) 1402 on January 23, peaking at 0359 UTC. This flare triggered a proton event, resulting in an S3 (Strong) Radiation (Proton) Storm and a Polar Cap Absorption (PCA) event over the polar regions.
This PCA event caused a complete radio blackout over high-latitude and polar regions. This results in any trans-polar radio paths to become as dead as a rock. This solar proton radiation storm is the strongest of the current solar cycle.
In addition, NOAA's Space Weather Prediction Center said plasma from an associated coronal mass ejection was expected to arrive on January 24, with storm conditions extending into the 25th.Watch for additional degradation of HF radio conditions and enhanced auroral conditions on VHF.