Solar Flare 10-Sept-2017 WSPR

X8.3-Class y un apagon de radio 

La gran emisión de Rayos X produce una ionización extrema de la Capa E de la Ionósfera bloqueando el camino de las señales a la capa F y por ende generando un bloqueo. Justo se dió que el fenómeno alcanzó la Argentina cuando era de día pudiéndose corroborar el bloque.

De manual SWS Australia:

Short Wave Fade-outs (SWFs)

Radiation from the Sun during large solar flares causes increased ionisation in the D region which results in higher absorption of HF radio waves (Figure 3.1). If the flare is large enough, the whole of the HF spectrum can be rendered unusable for a period of time. Fade-outs are more likely to occur around solar maximum than at solar minimum. The main features of SWFs are:

• Only circuits with daylight sectors will be affected;

• Fade-outs usually last from a few minutes to a few hours, with a fast onset and a slower recovery. The duration of the fade-out will depend on the duration of the flare;

• The magnitude of the fade-out will depend on the size of the flare and the position of the Sun relative to the point where the radio wave passes through the D region. The higher the Sun with respect to that point, the greater the amount of absorption;

• Absorption is greatest at lower frequencies, which are the first to be affected and the last to recover. Higher frequencies are normally less affected and may still be usable (Figure 3.2).

Short-wave fadeouts are also called daylight fade-outs or sudden ionospheric disturbances (SID).

Fade-outs affect lower frequencies the most and these are the last to recover. Higher frequencies are least affected and sometimes unaffected by smaller flares.