Black Hole

A Black Hole in Universe Sandbox is a simulated object representing an actual black hole, or a new black hole created by the user.

A Galaxy object is made up of several Galaxy Nebula objects and a single Black Hole (see Galaxy Structure). A Black Hole in a Galaxy will exert a gravitational force on other objects in the simulation based on the total mass of the galaxy, rather than the mass of the Black Hole itself.

Black Hole objects have the following sets of properties:
 * They are attracting objects, meaning that they exert a gravitational force on other objects in the simulation.
 * They are attracted objects, meaning that they feel the effects of gravity from other attracting objects in the simulation.
 * They have calculated orbital elements, and their orbit can be displayed.
 * They can collide with other objects.
 * They have a simulated composition.