This image of the Sun was taken with a hydrogen-alpha telescope at the Phoebe Waterman Haas Public Observatory at the National Air and Space Museum in Washington, DC, at 12:00 pm on January 9, 2015.
The dark lines on the disk and protrusions around the edges are magnetic loops that extend into the atmosphere of the Sun. When they appear on the disk, they are referred to as filaments; when they are on the edge, they are called prominences. There are also several sunspot groups. At the time of this picture, the largest sunspot group, AR2257, was growing more unstable and had the potential for M-class and X-class solar flares.
Sunspot AR2257 erupted several days later, on Jan. 13th, producing an M5-class solar flare that caused brief communications blackouts over Australia and the Indian Ocean.
Telescope: Lunt 100mm hydrogen-alpha
Camera: Lumenera SKYnyx 2-2M