Mesklin
Alongside the novel's original 1953 serialization in Astounding Science Fiction, Clement published an essay titled "Whirligig World" detailing the process of designing the planet to have the properties he wanted.
[4]: 215 [16] Clement later wrote an additional three fictional works using the planet or its denizens: the sequel novel Star Light (1971; originally serialized in Analog Science Fiction/Science Fact, June–September 1970) and the short stories "Lecture Demonstration" (1974) and "Under" (2000).
[18][19] In "Whirligig World", Clement encouraged other authors to use Mesklin as a setting for their stories provided that they stay within "reasonable scientific standards", while acknowledging that to be "certainly an elastic requirement in the field of science fiction".
[1]: 107 [20] Clement drew inspiration from astronomical work published in 1943 by Kaj Aage Gunnar Strand, whose analysis of the motion of the two known stars in the 61 Cygni system indicated the presence of a third, unseen object of relatively small size and mass.
[21] At the time, it was unclear whether the object would behave more like a very low-mass and faint star (a brown dwarf) or a high-mass planet (Super-Jupiter); Clement elected to depict Mesklin as the latter in order to be able to use it as a setting for his story.
[21][23]: 35 Clement decided to reduce the effective gravity by providing the planet with a rapid rate of rotation to make it possible for humans to land on it in the story.
[10][21] He settled on an effective equatorial gravity of 3 g and worked backwards from there to calculate the spin that would result in the centrifugal force necessary to offset the correct amount of the planet's gravitational pull.
[25] Based on the observed orbit of 61 Cygni C and the known properties of the stars in the system, Clement calculated that the planet would be very cold at an average temperature of −170 °C throughout the majority of its year, with a low of −180 °C and a high of −50 °C.
[11]: 73 [22][23]: 35–36 He enlisted the help of biochemistry teacher and fellow science fiction writer Isaac Asimov, and together they worked through various alternatives such as carbon disulfide (CS2) and hydrogen fluoride (HF) before settling on methane and developed a basic outline for the kind of ecosystem and lifeforms that could plausibly exist in such a chemical environment.
[26]: 170 Stephen L. Gillett [Wikidata], writing in The Greenwood Encyclopedia of Science Fiction and Fantasy (2005), described Mesklin as the prototypical example of an alien world vastly dissimilar to Earth.
Pierce, writing in 1987, commented that it far surpassed the exotic settings imagined in works like Stanley G. Weinbaum's "Parasite Planet" (1935) and E. E. Smith's Lensman series in terms of its alienness.
[8]: 1426 Morgan further commented upon the Mesklinites' human-like thought processes and their desire to gain scientific knowledge while at the same time seeking to avoid giving up their independence.
In Morgan's view, these things make the Mesklinites more reminiscent of an "emerging third world country" than a wholly alien species;[4]: 218 Barron similarly identified a native–colonist analogy.
[9]: 89 Hassler further compared the depiction of the Mesklinites to the works of Jonathan Swift, both in terms of the size differential as in Gulliver's Travels (1726)—calling them "Lilliputians in a Brobdingnagian world"—and their use as a vehicle for social commentary.
Nevertheless, Westfahl did not find Mesklin to be characterized effectively in the novel, which he attributed to Clement's decision to reveal information about the planet piecemeal in an indirect and roundabout way.
