This image of the Sun was taken on July 25, 2012 at 12:50 pm, shortly before the Observatory opened for public observing.
The image is taken with a hydrogen-alpha camera, which only lets through a particular color of red light which reveals features of the atmosphere of the Sun.
The most notable feature that day, which persisted for days, was a giant prominence on the upper left edge of the Sun's disk. The arch of plasma stands about five to ten times as tall as the Earth. The plasma streams above the Sun along magnetic "highways."
Telescope: Lunt 100mm Hydrogen-alpha
Camera: Lumenera SkyNYX 2-2M
Image Number: WEB12558-2012
Credit: Image by Emily Berkson, Smithsonian Public Observatory Project
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