What is a "Blood Moon"?
Quick Answer: A Blood Moon is a total lunar eclipse when Earth's shadow makes the Moon appear reddish. This happens because sunlight passing through Earth's atmosphere bends and filters, casting a red glow on the Moon’s surface.
During a total lunar eclipse, the Earth is directly between the Sun and the Moon. The Moon moves into Earth's shadow, blocking direct sunlight. However, some sunlight still reaches the Moon after passing through Earth's atmosphere.
The atmosphere scatters blue light but allows red and orange light to pass through, which tints the Moon with that eerie red color. This reddish hue is why it’s called a "Blood Moon."