Important notice about STEREO Behind
Smaller active regions in 3D
This 3D image shows one distinct and a few smaller active regions that appear brighter in the 195 Angstroms wavelength of extreme UV light. It was made by combining two EUVI 195 images from the Ahead STEREO spacecraft about 11 hours apart on April 27, 2008. (Note, it is not true 3D which would need to be taken from two perspectives at the same time. Since the Sun's rotation moves the features and these features do not change that quickly, this 3D effect can be achieved.) The arcing lines extending above the largest active region show the flow of particles along powerful magnetic field lines that rise above the Sun's surface. Active regions, which are seen as sunspots in visible light, are areas of intense magnetic activity that can last days or even months. The darker areas are small coronal holes.
Right and Left Images
Last Revised: March 19, 2018 15:00:39 UTC
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