
Universe Modeler supports collision detection of objects.  This is very useful
to create realistic scenes where objects in the scene rest on top of one
another, and yet don't go through each other.

Collsion detection is activated when you are moving ACIS bodies using the 
move/rotate/scale tools, by holding down the "C" key while transforming the 
object. 

To get very accurate collision detection, zoom in closer and then transform
the object, so that you are moving the object a very small distance for each
collision detection step.
