It's showing a sunspot, which is cool (pun intended), but more interestingly to me, you can clearly see granulation. The spiderweb-style cells are convective cells; the bright centers are hot gas, which is still rising, and the dark edges/divisions are the cooler gas, which is sinking. This is the result on convection, which occurs from about 0.7 R_Sun up to 1 R_Sun, even though the core of the Sun is radiative.

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