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For the first time, scientists have shown that solar flares produce seismic waves in the sun's interior that closely resemble those created by terrestrial earthquakes. The researchers observed a flare-generated solar quake that contained about 40,000 times the energy released in the great earthquake that devastated San Francisco in 1906.
Alexander G. Kosovichev, a senior research scientist from Stanford, and Valentina V. Zharkova from Glasgow University found that the solar quake recorded by a NASA/European Space Agency spacecraft looked much like ripples spreading from a rock dropped into a pool of water. But the solar waves were nearly two miles high and, over the course of an hour, traveled a distance equal to 10 Earth diameters before fading into the fiery background of the sun's photosphere. Unlike water ripples that travel outward at a constant velocity, the solar waves accelerated from an initial speed of 22,000 miles per hour to a maximum of 250,000 mph before disappearing. It would take a magnitude 11.3 quake on Earth to unleash an amount of energy equivalent to that released by the solar quake. That is enough energy to power the United States for 20 years at its current level. Now that the scientists know how to find solar seismic waves, they say they will be able to verify some of the conditions in the solar interior they have inferred from the pattern of waves that continually ruffle the sun's surface. For more information visit the Solar Oscillations Investigation website at http://soi.stanford.edu/.
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