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.

According to Dr. Angela Speck, a professor of astrophysics and department chair for physics and astronomy at The University of Texas at San Antonio, the "blood moon" total lunar eclipse was visible across the U.S. and no special equipment was necessary to view it.

In the Americas alone more than one billion people in 35 countries could bear witness to the total lunar eclipse.