How will the sun be folded up and what will its shape be like then, and what will the shape of the sky be like when it is split asunder?

The "takweer" (coiling/darkening) of the sun means its wrapping up, gathering, the departure of its light, then its being cast into the sea, or its disintegration, or its gathering with the moon and both being cast into the Fire. As for the "inshiqaq" (splitting asunder) of the heavens, it means their cracking, the disruption of their order, the scattering of their celestial bodies, the falling of their stars, and the eclipse of their sun and moon. All of this expresses a tremendous cosmic upheaval that occurs at the advent of the Hour, where "the earth will be changed to other than the earth, and the heavens as well."