Giant solar waves spew more energy than 10 bn atom bombs

March 21st, 2009 - 4:46 pm ICT by IANS  

London, March 21 (IANS) Scientists have detected vast turbulent waves in the sun’s lower atmosphere that at a time spew the energy equivalent of 10 billion nuclear warheads.
Queen’s University Belfast (QUB) scientists with researchers from the Universities of Sheffield and California State, have shed some light on why the corona, the region around the sun, has a much higher temperature than its surface - something of a puzzle to scientists.

Their discovery has revealed the existence of a new breed of solar waves, called the Alfven wave, known to transport energy into the corona.

The surface of the sun, known as the photosphere, can reach temperatures of 5,000 degrees Celsius. But the corona has been shown to reach temperatures of over a million degrees Celsius.

The waves have been named after Hannes Alfven who in 1942 received a Nobel Prize for his work in the area.

He theorised the existence of these waves but no hard evidence ever surfaced, until recently, when Mihalis Mathioudakis, a professor and David Jess, both of QUB, made the discovery using the Swedish Solar Telescope in the Canary Islands.

Mathioudakis, leader of the Queen’s University Solar Group, said “The solar corona, visible from earth only during a total solar eclipse, is a very dynamic environment which can erupt suddenly, releasing more energy than 10 billion atomic bombs.

“Our study makes a major advancement in the understanding of how the million-degree corona manages to achieve this feat.”

David Jess, from QUB and lead author of the paper said: “Often, waves can be visualised by the rippling of water when a stone is dropped into a pond, or by the motions of a guitar string when plucked,” according to a QUB release.

“Alfven waves though cannot be seen so easily. In fact, they are completely invisible to the naked eye. Only by examining the motions of structures and their corresponding velocities in the Sun’s turbulent atmosphere could we find, for the first time, the presence of these elusive Alfven waves.”

These findings were published in Science.

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