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02/09/2018

A Powerful Solar Flare - Astronomy picture of the day - 2018 September 2

A Powerful Solar Flare 
Video Credit: SOHO ConsortiumLASCOESANASA
Explanation: It was one of the most powerful solar flares in recorded history. Occurring in 2003 and seen across the electromagnetic spectrum, the Sun briefly became over 100 times brighter in X-rays than normal. The day after thistremendous X 17 solar flare -- and subsequent Coronal Mass Ejection (CME) -- energetic particles emitted from the explosions struck the Earth, creating auroras and affecting satellites. The spacecraft that took these frames -- SOHO-- was put in a turtle-like safe mode to avoid further damage from this and subsequent solar particle storms. The featured time-lapse movie condenses into 10 seconds events that occurred over 4 hours. The CME, visible around the central sun-shade, appears about three-quarters of the way through the video, while frames toward the very end are progressively noisier as protons from the explosions strike SOHO's LASCO detector. One this day in 1859, the effects of an even more powerful solar storm caused telegraphs on Earth to spark in what is known as the Carrington Event. Powerful solar storms such as these may create beautiful aurora-filled skies, but they also pose a real danger as they can damage satellites and even power grids across the Earth.

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