This demonstration shows a team of Aerial Robotic Workers (ARW)s performing a circumnavigation mission. The ARWs circumnavigate a virtual target whose position is progressively estimated by means of event-triggered bearing measurements. The control objective is that the ARWs circumnavigate the target at a desired speed, while forming a regular polygon around the target. Each ARW maintains a running estimation of the position of the target, which is updated every time a new bearing measurement is taken. New bearing measurements are triggered with a recursive law that guarantees that the estimated position converges to the real position of the virtual target. Each ARW intermittently monitors the relative position of the ARW that precedes it in the circumnavigation, and adjusts its circumnavigation speed according to such relative position. This control logic allows the ARW to converge to a regular polygon around the target. The control algorithm is implemented on a ROS architecture where the controller of each ARW corresponds to a different ROS node.