Then, just after noon, a big storm caught me: yellow sun-flare, dulling to sepia.

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Another team of US physicists recently published a paper suggesting that an unusually large solar flare from the Sun could have caused the pulse of energy.

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The main suspect is a solar flare: the sun was acting up at that time, and several other satellites (owned by Germany, Japan, NASA and Motorola) all failed at the same moment.

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White House Science Advisor John Holdren and Sir John Beddington, Science Advisor to British Prime Minister David Cameron, in a recent joint article "Celestial Storm Warnings" published in the New York Times, warned that a solar flare from the Sun could cause a great geomagnetic storm, with catastrophic consequences for the United States and the world.

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When a massive solar flare erupts on the sun, it can cause geomagnetic storms on the Earth.

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Eichler thinks that such a sun-grazing comet may have triggered a large solar flare and cosmic ray-generating shockwaves as recently as 775 A.D.

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The sun has gone more than two years without a significant solar flare.

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The storm started with a massive solar flare Tuesday evening and grew as it raced outward from the sun, expanding like a giant soap bubble, scientists said.

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In February last year a large solar flare erupted, disrupting flights over Pacific, but the bulk of the material emitted by the Sun passed by Earth.

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