This image of the Sun was taken at 12:21 pm on February 6, 2013, through a beautiful blue sky.
At the Public Observatory at the Museum in Washington, DC, visitors were looking at sunspots using a white-light solar telescope, and seeing a view like this using a portable Hydrogen-alpha telescope. This image was captured using another Hydrogen-alpha telescope mounted piggyback on the Observatory's main telescope. A black-and-white version was also streamed live to the Web. The live view is usually available during Observatory hours when the weather is clear.
The sunspot near the center top is active, but decaying, and did not produce any significant flare activity while visitors watched. Visitors observed prominences extending from the edges of the Sun, and a conspicuous dark filament between the two sunspot groups.
Filaments and prominences are actually the same thing: arches of gas following magnetic loops above the Sun. When seen from above, they are dark, silhouetted against the bright Sun. When seen from the side, protruding off the edge of the Sun, they are bright compared to the blackness of space.
Telescope: Lunt 100mm Hydrogen-alpha
Camera: Lumenera SKYnyx2-2M
Image Number: WEB12717-2013
Credit: Image by Geneviève de Messières, Smithsonian Public Observatory Project
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