Can you tell me the methods used by planes to navigate before radar was invented?
user
A plane's position is determined by taking sightings of the sun and the stars.  This is called "nautical astronomy".  More complex techniques require "sextants" (which combine mirrors and telescopes), and work better on a moving ship, rather than an airplane.  Still, if an airplane is heading at constant speed, and the pilot's eye is aligned with the ship's axis of rotation, then at any given time there is a position on the "navigational sphere" (
assistant
Can you tell me the methods used by planes to navigate before radar was invented?
user
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assistant
Can you tell me the methods used by planes to navigate before radar was invented?