What's bright is dark.


Surprisingly those regions would appear dark in a normal, visible light photograph because they are regions where we would see sunspots.

Sunspots appear on the surface, or photosphere, of the Sun and are cooler than the surrounding area. Because they are cooler they appear darker.

So what the ultraviolet picture is telling us is that sunspots appear in regions (we call them "active regions") that appear cool near the surface but have a very hot cloud of gas hovering above them. Weird or what?


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