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These views of the Sun's outer atmosphere, at temperatures of some 80,000 degrees Celsius, show an eruptive prominence leaving the Sun's surface at a speed of over 50,000 miles per hour. When such eruptions are directed toward the earth, the resulting magnetic cloudscan deform the earth's magnetosphere, in some cases damaging geosynchronous satellites or even bringing down electric power grids.

The images were obtained by the Extreme ultraviolet Imaging Telescope (EIT) on the Solar and Heliospheric Observatory (SOHO) spacecraft. SOHO's unique "haloorbit between the earth and the Sun gives us our first uninterrupted view of the Sun's often violent outer atmosphere. Other SOHO instruments probe the invisible interior of the Sun and sample the solar wind flowing by the spacecraft. SOHO is a mission of international cooperation between the National Aeronautics and Space Administration and the European Space Agency. The EIT is a joint United States, French and Belgian effort.

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Executive Office of the President, Office of Science and Technology Policy

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