Did you ever watch the total solar eclipse?
When the Sun, Earth, and Moon are in a straight line, it can be called a lunar eclipse. It means the earth is between the Moon and the sun. Then, the sunlight is blocked. When the moon enters the shadow of the earth, the eclipses occurred.
This is because the Moon moves past the middle shadow of the Earth. This is the widest point of shadow, said Tim O’Brien, professor of astrophysics at the University of Manchester, England.