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Page 21. " a small planet in the vicinity of Betelgeuse "

Comparing the very ordinary town of Guildford with a planet somewhere near Betelgeuse is classic Adams technique.  Guildford is a large town in Surrey, a county in southern England.  Betelgeuse is one of the brightest stars visible from earth, located around 640 lightyears away.

guildford
Public DomainGuildford - Credit: S Knights