First 3-D stereo from STEREO: EUVI 171 Angstroms (Active Region)
This movie shows the Sun from the two STEREO spacecraft using the 171 Å filter in the Extreme UltraViolet Imager (EUVI). This filter reveals ionized iron (Fe+8=Fe IX, Fe+9=Fe X) which forms at temperatures above 1.3x106K, and flows along the magnetic field lines of the solar active regions. New regions of solar activity come into view as the Sun rotates left to right.