HUGE SOLAR FILAMENT: The biggest thing on the sun today is not a sunspot; it's a dark filament of magnetism. Stretching more than 350,000 km from end to end, the structure dwarfs any sunspot. It is noteworthy not only for its size, but also for its explosive potential. Oversized filaments like this one can become unstable and collapse, sparking Hyder flares and hurling CMEs into space.

https://imgur.com/iOLhT76

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