Eclipse Science 101

America is gearing up for the first coast-to-coast solar eclipse in nearly a century...but do you know what's actually happening?

(NBC News) Many, many moons ago a darkening sun in the middle of the day was seen as a bad omen.

In ancient China a dragon was said to eat the sun. Ancient Greeks thought a solar eclipse meant the gods were angry and imminent doom was certain.

Now, modern science proves total solar eclipses are nothing scary or surprising.

It’s a simple trick of geometry that makes the moon completely cover something 400 times bigger.

“The key is that the moon is 400 times closer to us, so it appears to be the same size, which allows us to have this beautiful solar eclipse,” explains Clemson University’s Dr. Amber Porter.

The stars must align perfectly for a solar eclipse. The sun, the moon and the Earth all in a neat row for the moon to cast its shadow on us.

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