Caliban's War

In the "frontier days" of human settlement of the Solar System, a superpowerful monster on Ganymede devastates the human colony as well as platoons of marines from Earth and Mars, fueling interplanetary tensions; but the crew of a spaceship recognize the handiwork of a technologically advanced alien artifact from the previous entry in the series, and join forces with an experienced but cynical UN official, a Martian marine who survived the attack, and a botanist whose daughter has been kidnapped, to identify and defeat the rogue tycoon who is attempting to use the artifact for his own purposes, and his allies in the Earth government.