Imagine that we are ancients and we know that the earth is s…
Imagine that we are ancients and we know that the earth is spherical because we have observed its shadow on the moon. In addition, we know that the earth rotates about its own axis because of the fact that we see day and night and the stars moving in circles around Polaris. Af- ter walking a distance of 100 km toward the north pole, we notice that the pole star is 1 degree higher in the sky. What is the circumference of our earth?