When the Earth, Moon, and Sun are lined up, it can cause two types of eclipses:

* Solar Eclipse: This happens when the Moon passes between the Sun and the Earth, blocking the Sun's light and casting a shadow on Earth.

* Lunar Eclipse: This happens when the Earth passes between the Sun and the Moon, blocking the Sun's light from reaching the Moon. This makes the Moon appear reddish-brown as it reflects light refracted through the Earth's atmosphere.