How you could measure Earth’s diameter using nothing but a shadow-casting stick, a protractor, and a car’s trip odometer if on a road trip between two cities that are approximately on the same line of constant longitude with a relatively straight shot of road connecting them.

How you could measure Earth’s diameter using nothing but a shadow-casting stick, a protractor, and a car’s trip odometer if on a road trip between two cities that are approximately on the same line of constant longitude with a relatively straight shot of road connecting them.
How you could measure Earth’s diameter using nothing but a shadow-casting stick, a protractor, and a car’s trip odometer if on a road trip between two cities that are approximately on the same line of constant longitude with a relatively straight shot of road connecting them.