# How do you measure the circumference of the earth using sun angles?

##### 1 Answer

Feb 1, 2016

This is a bit tricky...!

#### Explanation:

You need two spots on the surface of the Earth, A and B.

When standing at A you produce a shadow while standing at B (at the same hour of the day, say, midday) you do not produce a shadow.

You can evaluate, from trigonometry, the angle

and knowing the arclength

giving:

and then use

Hope it is understandable...