Have you ever wondered about the distance to the Moon? So have I. We can determine this distance from our measurements in challenge one. Here we calculated the diameter of the Moon to be approximately 3,600 km or 2,200 miles.

Next, we need to measure the angular diameter of the Moon in the sky. In other words, if a complete circle is 360 degrees, and a half-circle is 180 degrees, then what angle does the Moon cover in the sky? Ten degrees? Five degrees? What do you think? How could you measure it? Click HERE for some ideas.

Knowing the angular diameter of the Moon, we are ready to calculate its distance from Earth (using the angular diameter of the Moon and a little geometry). Consider the following ratio:

Using the actual diameter of the Moon (which you calculated in challenge one), can you compare this ratio to actual distances? Perhaps a hint will help: You will need to know how to calculate the circumference of a circle.

Click HERE for an explanation.


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