Scientists have used the ESA/NASA Solar Orbiter’s Extreme Ultraviolet Imager (EUI) in a new mode of operation to record part of the Sun’s atmosphere that has been almost impossible to image until now. By covering the Sun’s bright disc with an ‘occulter’ inside the instrument, EUI can detect the million-times fainter ultraviolet light coming from the surrounding corona.

This movie shows an ultraviolet image of the Sun’s corona taken using the EUI occulter. An ultraviolet image of the Sun’s disc has been superimposed in the middle, in the area left blank by the occulter. The image of the Sun’s disc has been taken by NASA’s STEREO mission, which happened to be looking at the Sun from almost the same direction as Solar Orbiter at the same time, so the features on the surface have a good correlation to the features in the corona.

The grid pattern is an artifact caused by the mesh that is holding the 150 nm thick front-filter. It is invisible in regular images but present (as expected) in occulter mode. The 'WOW-enhanced’ label next to the time counter in the lower left corner stands for the ‘Wavelets Optimized Whitening’ algorithm which enhances the visual appearance of the movie. 

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