Fade to Black

The Lord of Truth points us to this article, which neither he nor we understand...

"The idea is to try to answer the question of what does a black hole look like," said David Kornreich.

The simple answer is "black" because light cannot escape the gravitational pull of a black hole. But light traveling just outside a black hole will be bent -- similar to what happens in a lens.

Kornreich and his student Bryant Gipson have figured out how images of landscapes and planets would be distorted by having a black hole sitting in the foreground.

Such mathematical calculations have been done before for stationary black holes, but this is the first time it has been done for spinning black holes, Kornreich told SPACE.com. Most black holes in the universe are thought to be rotating -- many at high speeds.

In a stellar black hole, which forms when a giant star dies explosively, the rotation is a logical remnant of the star's spin. Just as a skater speeds up when she pulls her arms in, the dead star's rotation picks up dramatically as remaining material collapses into a small, dense black hole.

...The computations for a rotating black hole are complicated by the fact that space around the hole is forced to rotate with it. This so-called frame dragging will affect everything in the vicinity of the spinning black hole.

"Even light rays will get pulled along with the rotation," Kornreich said. "Those that run counter to the rotation sometimes don’t make it -- they get sent backwards."

Because some light rays are shot back at you, it is possible to see your own reflection if you look carefully at the side of the black hole rotating towards you, the thinking goes. But this does not mean astronomers will be able to see themselves through a telescope.

"This is something you would only see in a spacecraft as you approached a black hole," Kornreich said.

To observe these distortions one would have to be within about three or four times the black hole’s Schwarzschild radius, said Kornreich. For a non-spinning black hole, this radius defines the event horizon -- the sphere of gravitational no return for intrepid black hole investigators.

Frankly, these guys could be making up the whole thing, and I would have absolutely no clue. But that's much like the rest of my life.