Eclipses

An eclipse takes place when one heavenly body such as a moon or planet moves into the shadow of another heavenly body. There are two types of eclipses on Earth: an eclipse of the moon and an eclipse of the sun.

The moon moves in an orbit around Earth, and at the same time, Earth orbits the sun. Sometimes Earth moves between the sun and the moon. When this happens, Earth blocks the sunlight that normally is reflected by the moon. (This sunlight is what causes the moon to shine.) Instead of light hitting the moon’s surface, Earth’s shadow falls on it. This is an eclipse of the moon — a lunar eclipse. A lunar eclipse can occur only when the moon is full.