[Pharo-users] Making objects persistent

I am building a seaside application, and am in the process of building my models and unit tests. I have a few objects that build up my data by creating objects. when i run the data creation methods, everything is fine. immediately afterward, since these objects to belong to anything, they are cleaned up by garbage collection. is there a way to create these objects so that they persist? if this is possible, how would you go about deleting such a tenacious object? thanks!