Latitude-Dependent Laser Deconfliction and Geosynchronous Satellite Closures (Cerro Pachón vs. Equator)

Abstract

This video demonstrates the effect of observatory latitude on laser-satellite deconfliction patterns using simulated Program Approval Messages (PAMs) for the Robo-AO-2 laser system located virtually at Cerro Pachón (30.2408° S) and the Equator (0.0001° N). The animation highlights semi-static closure zones caused by geosynchronous satellites (~36 Mm altitude), showing how their apparent celestial positions shift based on site latitude—appearing toward the North from southern latitudes, toward the South from northern latitudes (e.g., Maunakea), and directly overhead along the celestial equator.