M-CLASS SOLAR FLARE: New sunspot AR2911 unleashed an M1-class solar flare during the early hours of Dec. 17th (0051 UT). A pulse of extreme UV radiation and X-rays ionized the top of Earth's atmosphere, causing a shortwave radio blackout over the South Pacific. There are now at least three sunspots on the solar disk capable of producing flares of this magnitude. Solar flare alerts: SMS Text.

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