It appears that if the Antarctica is destroyed without docking with it and going through the Helios talk screens it messes up the Terra screens when you return.

This error occurred once. See image.
The debug console had autoprinted:
OnBehaviorStart status: Nil behavior: Nil
And if it's any help scrGetScreen returned this:
{ data:{ missionObj:493735888 successOptions:Nil } pane:Success screen:"" }

At other times Decker says the Antarctica escaped and demotes you to MSgt even though the wreck is in the next system.

Also this may be intentional but the Terra seems to only ever appear in the system after Pt Juno and the Antarctica is always in Dantalion. EDIT: CSC Terra seen in other systems (Dantalion).