The Rovan Ruins — Michael McCloskey

The Rovan Ruins is the 11th book in the PIT series.

Avoiding their alien master at Sol, the PIT team has taken up new homes with the Celarans on a huge space habitat, aided by their Trilisk technology.

As they ponder their next move, they hear of new alien ruins in a distant system, discovered by a Celaran probe ship. Uncertain of their future, the PIT team decides to do what they do best, so they leave on a fresh voyage of discovery.