Now they just hang in space.
>>535792302
Nah that would only happen when you deleted the shell. They collapsed because they didn't have any obit at all and sort of fell towards the star instead. The current version even has them just fade away when you get too close.
I'm guessing this happened back when they did an optimization pass to help the save file size.
This sphere >>535791076
was more than a gigabyte per save.