This Video About The Scale Of Black Holes Will Crush Your Poor, Tiny Brain

Black holes are massive, matter-annihilating objects that appear to challenge physics by their very reality. They're so strange, that when Albert Einstein's equations first projected the actuality of these beasts, he didn't believe they could actually be real. But they are real. 

The video (below) beautifully gives a perspective of how big and mighty these monsters can become.