A broad term that can be defined as the significant lessening in brightness of one body due
to the motion of one or more others. Eclipses belong to a class of phenomena more properly called
occultations (literally, the 'hiding' of one body by another), but there are three classes of
occultation universally referred to as 'eclipses':
- A large body passing between the Sun and an observer, cutting off or reducing its light.
Solar Eclipses as observed on Earth belong to this type.
- The Earth's shadow passing across the face of the Moon, a relatively common
occurrence known as a Lunar Eclipse.
- One element of a binary star system passing in front of the other, thereby reducing the
magnitude of the entire system.