Fig6_8 Sun in X-rays

Fig6_8 Sun in X-rays

Fig. 6.8 . Ionized gases at a temperature of a few million K produce the bright glow seen in this x-ray image of the Sun. It shows magnetic coronal loops that thread the corona and hold the hot gases in place. The brightest features are called active regions and correspond to the sites of the most intense magnetic field strength. This image of the Sunís corona was recorded by the Soft X-ray Telescope, abbreviated SXT, aboard the Japanese Yohkoh satellite on 1 February 1992, near a maximum of the 11-year cycle of solar magnetic activity. Subsequent SXT images, taken about five years later near activity minimum, show a remarkable dimming of the corona when the active regions associated with sunspots have almost disappeared, and the Sunís magnetic field has changed from a complex structure to a simpler configuration. (Courtesy of NASA/ISAS/LMSAL/NAO Japan, U. Tokyo.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University