Why do lunar and solar eclipses not happen every month

Bottom line: There's no eclipse at every full moon and new moon because the moon's orbit is inclined to Earth's orbit by about five degrees. Most of the time, the sun, Earth and moon don't line up precisely enough to cause an eclipse

Explanation:

A lunar eclipse occurs when the Moon enters the Earth's shadow. A solar eclipse occurs when the Moon's shadow falls on the Earth. They do not happen every month because the Earth's orbit around the sun is not in the same plane as the Moon's orbit around the Earth.

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