Hi Joe, another of your stunning cut-away forms.
Because the charring on the sphere is (as far as I can see) perfectly circular, I see it as the effect of a lightning strike. Where the lighting hit, burnt and charred the wood then extinguished all very fast. Leaving the damage only in the area of effect, nothing inside the sphere and very little beyond the point of the strike.
I don't know why but I see it as a disturbing yet captivating object, very visceral, torn open and exposed, in a primitive way.