Exile, Book One of The Dark Mirror Trilogy. The Dark Mirror Trilogy

Exiled by choice. United by fate. Dr. Addison Lybrand's career ends the moment the object she's tracking vanishes beyond the heliopause. Discredited by her mentor and expelled from Earth by an authoritarian regime, she accepts a last, remote assignment: studying the object's lingering spatial distortions at Kuiper Station, the solar system's farthest outpost. Then Earth is attacked. Cut off from inner worlds and hurled into isolation ahead of schedule, Addison and three fellow exiles are left to survive on the edge of civilization.
When the object returns-closer, faster, and violently altered-they uncover a chilling truth: their exile may have been voluntary, but nothing else was. Every accusation, every banishment, every move has been engineered to drive them toward a single, impossible end.