Earth and the Moon


How does a lunar eclipse occur?

A lunar eclipse occurs when Earth passes between the Sun and the Moon in such a way that the Moon moves into Earth’s shadow. When a partial lunar eclipse is going on, the curved shadow of our planet is apparent on the Moon’s face; the Moon looks kind of like it is in a crescent phase, but the terminator line (the line between light and dark) is not curved the same way. When a total lunar eclipse is happening, the entire Moon is in Earth’s shadow, and the Moon looks full, but glows only faintly red.


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