I always loved thinking about why the moon is red during an eclipse:
During an eclipse of the moon, from the moon’s perspective, we’re eclipsing the sun. Much like when we look at the son during a solar eclipse, an astronaut on the moon wouldn’t just see a black disk – they’d see the sun shining from behind the earth.
But, unlike the moon, we have an atmosphere, one known for creating brilliant sunrises and sunsets. And, in fact, this is what our astronaut on the moon would be seeing: surrounding the Earth, all the sunrises and all the sunsets in the world, in one thin, giant ring of fire, casting its red light on the moon.
