Spacetime Paths Near the Black Hole (2) ...
The adjacent animation by Robert Nemiroff
illustrates some rather strange things that you would expect to see if you could
go near a black hole and orbit around it.
Gravitational Lensing Effects
In Chapter 4 we introduced the idea of gravity
acting as a lens because it can change the direction of light.
Because of the bending of light by the intense gravitational field,
very strong lensing effects can occur for black holes.
In this animation sequence, as one travels around the black hole defined by the dark
circle in the center, the apparent position and brightness
of stars is greatly distorted and multiple copies of images appear
because of the gravitational lensing.
For example, in most cases you can pick out a distorted copy of
a given image on the opposite side of the black hole. In one segment, many bright stars appear; these are mostly
the constellation Orion and a distorted copy on the opposite side of the black hole.
By using the animation controls to look at particular frames,
see if you can pick them out. Here is a more detailed
description of the adjacent animation.
