Harry Clement Stubbs

Stubbs kept two working lives deliberately apart: he taught science at a Massachusetts high school for decades, and he published fiction as Hal Clement. Mission of Gravity, serialised in Astounding through the spring and summer of 1953 and issued as a book the following year, is the one that fixed his standing. Mesklin is a planet spinning so fast it has flattened into a disc, and gravity on it runs from roughly three times Earth's at the equator to hundreds of times that at the poles. Barlennan, a Mesklinite trader built something like a centipede, contracts with humans to recover a lost probe from a polar region no human could survive. The physics is worked out first and the plot follows from it, which is close to what people mean by hard science fiction. He held degrees in astronomy, chemistry and education, flew as a bomber pilot in the war, and was named a Grand Master by the science fiction writers' association in 1998.