Satellites make it possible to identify and track seafaring vessels all over the world, covering the oceans and the Antarctic.
Ships of 300 tonnes or more in international voyages, cargo ships of 500 tonnes or more in local waters and all passenger ships irrespective of size are mandated by the International Maritime Organization to carry Automatic Identification System (AIS) equipment.
The international AIS is the maritime equivalent of air traffic control. This radio-based communications system was originally developed to prevent collisions of large vessels. It transmits the course and speed as well as identification and position information to other vessels and shore stations.
AIS is also included in Aids-To-Navigation and Search and Rescue transponders.
While AIS has been deployed globally, it suffers from a major limitation because Earth’s curvature limits its horizontal range to about 74 km from shore. This means that AIS traffic information is available only around coastal zones or on a ship-to-ship basis.
Tracking ships using microsatellites (SAT-AIS) solves this problem. The ship’s identity is recorded and decoded by satellite then sent to ground stations for further processing and distribution.
ESA is promoting SAT-AIS systems, technologies and services in partnership with the European Maritime Safety Agency, a regulatory agency established in the late 1990s along with a number of other major European maritime safety initiatives. It supports the European Commission and Member States in maritime safety services, such as the prevention of pollution from ships and tracking of dangerous goods.