Note 9 — Chapter VII · AURORA-LIKE PATCHES ON THE PARTIALLY-ECLIPSED MOON.

The proof from occulted stars merely goes to the fact that the moon possesses no atmosphere appreciable in that way. It may still be a question whether there does not exist something of the kind, lying low and close to the surface, and possibly of a rarefied character, which would scarcely make itself visible by its effects in occultations. Cloud-vapour might form in an atmosphere of inconsiderable density.