NOVA

There are apocalyptic objects out in the universe-deadly and mysterious. "What exactly is a black hole, and where do they come from?" "Black holes can sort of blow your mind." "I'm amazed that these objects actually exist." Totally invisible, yet impossibly powerful. "They're the most exotic objects in the universe. We don't have the physics to describe them."...shattering our concepts of time and space.

"A black hole is a place where there is nothing. Nothing except gravity." "You might think a black hole is like this-an object, not it's not. It's a hole in the fabric of space." Now, scientists are on the hunt for black holes-what we can see with our eyes is limited. "Galaxies can have a lot of dust and gas." But a space telescope is equipped with X-ray vision.

"X-rays bring into view regions of a galaxy that would otherwise be obscured."...and the death of a star is revealed. "The star that gets too close? What does the black hole do? It flays the outer layers, ultimately devouring the entire star." Can a radical observatory called LIGO detect a black hole collision?

"At one point three billion years ago, these black holes collided." "The collision creates an incredible storm in the fabric of space and time." A gravity wave explodes outward, racing at the speed of light. It travels over a billion light-years before reaching Earth. Inside these tombs, lasers must monitor impossibly tiny distances. "You are monitoring the motion of mirrors-minute amounts, ten thousand times smaller than the nucleus of an atom." The data reveals a warp in time and space.

"That wave is a new and direct evidence of the existence of black holes." Yet despite their destructive power, could the universe even exist without them? "Every galaxy, when we look for one, we have found a supermassive black hole in the center." "Black holes might well be the key players in the universe."