Schwere Welten (6678 041)

Blurb

Mission of Gravity is a science fiction novel by Hal Clement. The novel was serialized in Astounding Science Fiction magazine in April–July 1953. Its first hardcover book publication was in 1954, and it was first published as a paperback book in 1958. Along with the novel itself, many editions of the book also include "Whirligig World", an essay by Clement on creating the planet Mesklin that was first published in the June 1953 Astounding.
Clement published two sequels to Mission of Gravity, a 1970 novel called Star Light, and a 1973 short story called "Lecture Demonstration". Mission of Gravity was nominated for a "Retro Hugo" Award for the year 1954.