STEREO (Behind) observed in profile the bending and twisting loops above an active region as it rotates to and around the edge of the Sun over two days in EUVI 171 wavelength (Dec. 16-17, 2007).
A major solar 'superstorm' such as the one in 1859 could cost $30 billion a day to the US electrical power grid, and up to $70 billion to the satellite industry.