The Whole Universe Surrenders: Supernatural Exploration of Outer Space, Book 4

The Belcluugs are a scavenging conqueror, stealing the best of many planets' spacecrafts and easily destroying earth's defenses. Unwilling to sacrifice the Horizon, Captain Alicia headed to the Empty Expanse to develop a defense, pursued by the Belcluug mother ship. She may have found a solution, traveling back in time. However, she is pursued back in time by a Belcluug ship seeking her death.