Mesklin

The fictional planet Mesklin was created by science fiction author Hal Clement, and first featured in his 1953 novel Mission of Gravity, later appearing in the short stories Under and Lecture Demonstration, and its creation elaborated upon in the article Whirligig World.

Based on the mass and orbital characteristics of a planet then surmised to exist around 63 Cygni A, Mesklin is a massive superjovian planet with an extremely rapid rotation rate. These characteristics lead to the planet's significantly oblate (flattened) shape and considerable difference in gravity between the equator (3G) and the poles (over 200G).

With a surface temperature much lower than that on Earth, Mesklin is home to a biosphere based on liquid methane rather than water, including the native Mesklinites, a centipede-like intelligent species well adapted to the extreme conditions of their world.