I've been using the center of mass feature in a large assembly and just noticed the COM can not be seen in the assembly model while it was visible for weeks before this.  The COM of subassemblies is visible, but not the COM of the overall assembly.  I have tried deleting the COM, and creating it again and while a COM shows up in the design tree, the COM is not visibile in the model.  The COM is not hidden, it just can't be seen.  When I right-click on COM in the design tree and pick zoom to selection, it zooms to the area in the model where the COM should be, but it is not visible.   I've tried hiding and showing, deleting and recreating it and still nothing.

Any ideas how I can get the COM visible again?