What causes eclipses?

Eclipses occur when one celestial body blocks light from another, as seen from Earth. A solar eclipse happens when the Moon passes between the Sun and Earth, casting a shadow on Earth. A lunar eclipse occurs when Earth moves between the Sun and the Moon, causing Earth’s shadow to darken the Moon. The alignment must be perfect, which is why eclipses are relatively rare. The type and duration of an eclipse depend on the distances and relative positions of the Sun, Moon, and Earth.