That the moon and the sun, even though they have these vastly different diameters, that they look roughly the same size in the sky because the ratio of the distances is comparable to the ratios of their diameters. This gives me goosebumps whenever I think about it because it didn't have to be this way. But what's neat is, and this depends on where earth is in its orbit, but this is approximately equal to 108. And this number is roughly 400 times larger than that number. So this number is roughly 400 times larger than that number. It's approximately the same as the ratio between the distance from earth to the sun which would be 93 million miles over 865,000 miles in diameter. So, for the moon, that ratio, the distance to the moon, 239,000 miles over the radius of the moon, 2,200. Now one thing that is very interesting, this is why the moon looks like it's the same size as the sun in the sky, even though it is one four hundredth of the diameter, is the ratio between the distance to the moon and the diameter of the moon is roughly the same as the ratio of the distance of the sun to the diameter of the sun. Now the distance between the two is 239,000 miles. So, a little bit more than one fourth the diameter of earth. While the moon has a diameter of approximately 2,200 miles. Earth has a diameter of approximately 8,000 miles. Right over here is a scaled picture of the distance between the earth and the moon. When you look at the moon in the night sky, it might seem reasonably close.

Lunar phases