The doxography for Xenophanes of Colophon unambiguously attributes to him a theory that all the meteora, i.e. all 'objects suspended above us' or 'objects seen in the sky' are different types of clouds. My concern in this paper is with two sets of assumptions that are likely to have framed Xenophanes' theory: a) assumptions concerning the size and shape of the eareth, and b) assumptions concerning the motions of the fixed stars.
Mourelatos, Alexander P.D., "Earth and Stars in the Cosmology of Xenophanes" (2000). The Society for Ancient Greek Philosophy Newsletter. 395.