Black Hole Approach : This animation shows how counter intuitive a black hole approach probably looks like due to the strong gravitational lensing. The redshift in light occurs where light is traveling away from the observer and the blueshift where it is coming towards. The accretion disk consists mainly of plasma and last pieces of very hot matter. This animation is so to say slow motion as it would actually move close to the speed of light. (Credit: Michael Biebl)