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Vessels Caught in ‘Circle Spoofing’ Off West Coast

One of the great technological advancements of modern-day sailing is the ability to watch a vessel’s track as it makes its way around the world. AIS (Automatic Identification System) is a tracking system used by thousands of private and commercial vessels that not only keeps family and friends abreast of your travels, but also provides an additional layer of safety by enabling other vessels to see you, long before you can see each other physically. And for those of us who have spent any time at sea, it can be a great comfort to know that someone is watching. But what happens when the AIS is wrong?

This image from the Marine Traffic website shows only some of the thousands of vessels making their way across the oceans at any given time.
© 2020

In a recent observation, a number of vessels have been reported to be circling northwest of San Francisco, and off Madrid, Hong Kong and China, while their physical locations are thousands of miles away in other parts of the globe. The discovery, loosely coined ‘circle spoofing’, appears to be related to similar incidents previously observed in China and Iran. But researcher Bjorn Bergman of SkyTruth, a nonprofit organization based in West Virginia, says his search for an explanation is hampered by the lack of “commonality between the vessels and incidents.”

One of the circling vessels was reported to be drifting inland to Utah.
© 2020

While the phenomenon remains a mystery, the Resilient Navigation and Timing Foundation (RNT) is hoping to hear from people who have ideas or insights that could help solve the mystery. Follow the link to read more:


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