Could you check to see if you can reproduce this problem?
Does it get stuck with the slightest inconvience (ie. does the Terror Star have to make a slight adjustment in its path to get around it)? Were there lots of things in its way, so it could not of may a simple course correction?
If you can manage to reproduce it, could you make a save before it happens, zip it up, and send it in an e-mail explaining what you have to do to get this stuck turn.
E-mail to:
gc2bugs@stardock.com