Flare Affecting Radio Transmissions

LIMB FLARES: The northwestern limb of the sun is crackling with M-class solar flares. The source appears to be departing sunspot complex 1280-1286. Coronal mass ejections (CMEs) emerging from the blast site are not Earth-directed. Nevertheless, these flares are having a minor effect on Earth as their radiation ionizes our planet’s upper atmosphere. For an example, see “Radio-Altering Flare” below 

RADIO-ALTERING FLARE: On Sunday morning at 1145 UT, an active region on the sun’s western limb unleashed a strong M3-class solar flare. NASA’s Solar Dynamics Observatory recorded the flash of extreme ultraviolet radiation:

Although the blast site was not directly facing Earth, radiation from the explosion nevertheless ionized Earth’s upper atmosphere. This altered the propagation of radio signals around Europe, where it was high-noon at the time of the flare. “I detected a sharp change in signal levels from two radio stations on the VLF band,” reports Rob Stammes of Lofoten, Norway. More radio anmolaies were detected by Dave Gradwell in Ireland (data) and a team led by Valter Giuliani in Italy (data). This shows that flares can affect our planet even when the underlying explosions are not “Earth-directed.”

fr/spaceweather.com