Hal Clement's "Whirligig World" (essay)

Author describes the rigorous process, including consultations with Isaac Asimov & others, he went through in designing Mesklin, the world at the heart of "Mission of Gravity".

He also tells us: "I hereby give official permission to anyone who so desires to lay scenes there." "there" is Mesklin; according to the article, you can set a story there without worrying about copyright violations, provided that you "maintain reasonable scientific standards, & that's certainly an elastic requirement in the field of science fiction."

First published: Astounding, June 1953.
Related: Stories of Hal Clement.