Solar activity. Gradient filter of the Sun with various phenomena visible, including coronal loops. Gradient filters are used to enhance the contrast of an image, in this case highlighting details of the solar activity. Around the edge of the Sun is the glow of the solar atmosphere (corona, white). Eruptions, such as coronal mass ejections and loops (orange), are seen rising from the surface. The image data is from NASA's Solar Dynamics Observatory (SDO), obtained in the ultraviolet part of the spectrum. Image published in 2012.