Containment by Susan Kaye Quinn

The Mining Master of Thebe is all alone… not counting the scavenger drones, foundry nanites, and magtread tractors buzzing across the tiny Jovian moon. So when a spindly tower of rocks mysteriously appears at the pole, it’s enough to vex the Mining Master’s machine-sourced intelligence like dust trapped in a harvester joint. Reporting it could mean reassignment to the Outer Belt… but probing the mystery further threatens to unlock something that might have been better left… contained.