Ever wondered why you shouldn't look directly at the sun? This is why.

Warning: Video contains graphic imagery.

Remember how your mother warned you never to look directly at the sun? Turns out, she was 101 percent correct.

On May 9, an astronomical event that only takes place around 13 times a century will occur: The planet Mercury will travel between the Earth and the sun.

Spectacular phenomena like this often encourage amateur astronomers to break out their dusty telescopes and take a peek. Inevitably, someone will forget just how bad an idea it is to look straight at the sun, whether through the naked eye or a telescope.

That's why Mark Thompson, a British astronomer and author, has put out a very graphic public service announcement. In the video, he exposes a pig's eye to sunlight through the eye piece of a telescope. By the time it starts smoking, as the sun quickly burns a hole through the cornea, you should have learned your lesson. Read more...

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