Survey drones GLMZ-NAV-112 and GLMZ-NAV-113 were deployed on parallel mapping runs along the southern perimeter on August 1st, 2212. Standard procedure: the drones fly programmed routes with GPS guidance, LIDAR terrain mapping, and inertial navigation backup. The routes were 40 kilometers apart. The drones have no communication with each other during flight. They returned with mapping data that was accurate to within normal tolerances — except for a consistent deviation.

Both drones deviated from their programmed routes in the same direction: 0.003 degrees north-northeast. The deviation is tiny — over a 200-kilometer flight path, it amounts to approximately 10 meters of drift. It is also inexplicable. GPS guidance should have corrected any drift in real-time. The GPS was functioning normally. The drones' navigation logs show that they believed they were on course. Their instruments said they were on course. They were not on course. They were both 0.003 degrees north-northeast of where they should have been, consistently, for the entire flight.

We ran the flights again. Same deviation. We swapped the drones' routes. Same deviation. We replaced the drones entirely. Same deviation. We replaced the GPS modules, the inertial navigation units, the flight computers. Same deviation. We flew the routes with a manned vehicle using independent navigation equipment. Same deviation. 0.003 degrees north-northeast. Every flight. Every vehicle. Every instrument.

Something in the southern perimeter is pulling every navigation system 0.003 degrees north-northeast. It is not magnetic — our magnetometers show normal field values. It is not gravitational — our gravimeters show normal readings. It is not a GPS error — the GPS satellites are verified accurate from other locations. The deviation exists only in the southern perimeter, only in the north-northeast direction, and it is exact to six decimal places. Every model we build to account for it introduces new errors. The deviation is simpler than our explanations. It simply is.