This image of the sun was taken on July 15, 2015, with the Extreme Ultraviolet Imager onboard NASA's Solar TErrestrial RElations Observatory Ahead (STEREO-A) spacecraft, which collects images in several wavelengths of light that are invisible to the human eye. This image shows the sun in wavelengths of 171 angstroms, typically colorized in blue. via NASA http://ift.tt/1I5RgRI