The Vessel-ID System investigation on the International Space Station demonstrated the ability for a space-based radio receiver to track a ship’s Automatic Identification System (AIS) signal, the marine equivalent of the air traffic control system.
Since being turned on in 2010, Vessel-ID has been able to relay more than 400,000 ship position reports from more than 22,000 ships in a single day, proving a quantum leap in the ship tracking ability of coast guards around the world.
This ability, coupled with multiple AIS tracking satellites launched since, is already making travel among the waves safer for thousands of ships around the globe. The ship identification and tracking system technology already aided in orienting rescue services for a lone survivor stranded in the North Sea, giving new hope to once impossible situations.
Reference : NASA