A total lunar eclipse will make the moon appear red across the Western Hemisphere during the "Blood Worm Moon" this week.

As the moon reflects the sun's light, the shadow dims the moon's glow. During the peak of a total lunar eclipse, the moon takes on a bit of a reddish hue as any leftover sunlight making it to the moon's surface is scattered by our earth's atmosphere.

Stargazers on nearly one half of the world witnessed a total lunar eclipse overnight, as a rare cosmic lineup caused the moon to turn a shade of red.