A composite picture shows what the sun's atmosphere looked like on Wednesday, as seen in three different wavelengths of light. The picture—assembled from shots taken by the Atmospheric Imaging Assembly instrument aboard NASA's Solar Dynamics Observatory—includes a model of what the sun's magnetic field lines looked like at the time.
One of three main instruments on the orbiting observatory, the AIA takes pictures of the sun in ten wavelengths every ten seconds. Overlaying several such images can show how magnetic events, such as prominence eruptions and coronal mass ejections, generate motion across the solar orb.
(Also see the sharpest picture of a sunspot yet taken in visible light.)