PHOTOS: Weird and Wonderful SOHO Observations
After the crescendo of solar maximum peaks, the sun's global magnetic field begins to ebb, eventually reaching "solar minimum", when the sun settles into a quiescent state. We are currently experiencing the downward slope to quiescence since the sun hit solar maximum around 2012-2013. But as you can see from this beautiful portrait, the sun certainly isn't going quietly.
The Solar Dynamics Observatory has just started its sixth year of operations (it was launched on Feb. 11, 2010), continually staring at the sun, revealing never-before seen dynamics in the sun's outermost layers and its extended corona. This particular series of observations were recorded using the AIA instrument's 171 angstrom filter. The emissions from the corona at these wavelengths are produced by plasma heated to over 1 million degrees Kelvin (Celsius). Active regions are a hotbed of coronal heating and therefore appear bright to the 171A filter.
As a comparison to the composite image, here's a raw single observation from SDO as captured earlier today: