Powerful magnetic waves have been confirmed for the first time as major players in the process that makes the sun's atmosphere strangely hundreds of times hotter than its already superhot surface. The magnetic waves — called Alfven waves — can carry enough energy from the sun's active surface to heat its atmosphere, or corona. "The surface and corona are chock full of these things, and they're very energetic," said Bart de Pontieu, a physicist at the Lockheed Martin Solar and Astrophysics Laboratory in California. The sun contains powerful heating and magnetic forces which drive the temperature to tens of thousands of degrees at the surface — yet the quieter corona wreathing the sun reaches temperatures of millions of degrees. Scientists have speculated that Alfven waves act as energy conveyor belts to heat the sun's atmosphere, but lacked the observational evidence to prove their theories. De Pontieu and his colleagues changed that by using the Japanese orbiting solar observatory Hinode to peer at the region sandwiched between the sun's surface and corona, called the chromosphere. Not only did they spot many Alfven waves, but they also estimated the waves carried more than enough energy to sustain the corona's temperatures as well as to power the solar wind (charged particles that constantly stream out from the sun) to speeds of nearly 1 million mph.However, the chromosphere findings alone could not prove the waves carried their energy into the sun's atmosphere.
View: Full Article | Source: Space.com
