ISS Can Now Watch Sea Traffic From Space 89
gyrogeerloose writes "During its last mission, astronauts from the Space Shuttle Atlantis installed an Automatic Identification System antenna on the outside of the International Space Station that will allow astronauts aboard the ISS to monitor signals from the AIS transmitters mandated to be installed on most large ocean-going craft. Although these VHF signals can be monitored from the Earth's surface, their horizontal range is generally limited to about 75 km (46 mi), leaving large areas of the ocean unwatched. However, the signals easily reach the 400 km (250 mi) orbit of the ISS. The European Space Agency sees this experiment as a test platform for a future AIS-monitoring fleet of satellites that will eventually provide worldwide coverage of sea traffic."
Tracking coastal AIS vessels (Score:5, Informative)
There are several websites that show at least coastal traffic of all AIS equipped vessels. I like http://www.marinetraffic.com/ais/ [marinetraffic.com]
Coverage map (Score:5, Informative)
Here's the map of existing coverage. [marinetraffic.com] The continental US, Europe, and Japan, have full coastal coverage. The port coasts of China and Australia are covered. Beyond that, not so much.
This isn't a safety system. It's for traffic and port management. Vessels show up in the system around the time when ports need to start thinking about where to put them.
No surprise really (Score:2, Informative)
This is a pretty common and extremely cheap sensor to put in space. Multiple tiny satellites have demonstrated the utility of an AIS sensor in space.
In space these are mainly used to track ships who might be up to no good on open water. Also you can fuse the data with radar satellite wake detection, any detected ship with their signal turned off also might be up to no good. Canada is doing just this with M3MSat and Radarsat-2
Re:Coverage map (Score:2, Informative)
That's just the coverage available on one particular website. (Other sites can have different data sources and different coverage.) Also, those rectangles just mean that there is some coverage within the rectangle. (Often, coverage is available around larger cities and a lot of the area is not covered.)
Furthermore, AIS is sometimes used for collision avoidance, so it is used for safety.