What can cause the full Moon to quickly darken, then glow red? A lunar eclipse: a striking display of orbital mechanics that occurs when the Moon passes through the Earth's shadow. To learn more, watch the video below.
It's not often that we get a chance to see our planet's shadow, but a lunar eclipse gives us a fleeting glimpse, as the Earth's shadow is projected onto the full Moon over the course of a few hours. Though a lunar eclipse can be seen only at night, it's worth staying up to catch the show.