[#3Fan]

Look again. One side is blasted off. Just like earth. Where is the missing crust?

This picture seems to show plastering though: Plus topographical studies show that the plastered side is sitting on top of the exposed unplastered side.

[#3Fan]

Plus topographical studies show that the plastered side is sitting on top of the exposed unplastered side.

Let me rephrase that. Topographical studies (or studies of the crust) show that the loose pastered debris is sitting on top of a former surface that is visible on the unplastered side.