What Is That Big Black Dark Circle Blotting Out the Sun?

During total eclipses of the sun, what is that big black dark circle blotting out the sun? They say it's the moon. But shining on the night side of the moon during a total solar eclipse would be the sun's reflection off the Earth. Full sunlight is about 10,000 times brighter than Earth's light on the moon. And now we get into the whole thing, you know, why? Well, there are no stars in the Apollo images and all that. It's because of technology.