Schwarzschild Black Hole
JP Schneider stashed this in There's Science in This Shit
A black hole is an extreme astronomical object that is the final stage of the evolution of some stars. Its gravitational field is so intense that it bends the path of light rays, giving rise to visible distortions. This is a simulation of what you would see when at close distance from such an object, on the backdrop of the Milky Way.
The most prominent feature is the black, featureless disc. This is the Event Horizon, or rather the image of it; the EH is the so-called "surface of no return", a membrane that can only be crossed by ingoing objects. Since nothing, including light, can escape the EH, its image appears pitch black.
Around the EH, the whole sky is visible, distorted. Multiple images of the same objects can be seen. Occasionally, when the viewer, the BH, and a distant star are suitably aligned, the star's image is distorted in a thin ring of light called an Einstein ring.