ISS Can Now Watch Sea Traffic From Space
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."
So any bets on how long it'll take them to find a nefarious use for this? Like spying on any private boats passing within x leagues of Cuba? [/paranoia]
Unity? Screw that: XFCE. Slashdot Beta? Screw that: SoylentNews. Australis? Screw that: Pale Moon. UX developers DIAF
How long before I get pulled over for speeding in the trade lanes?
Where else would they be watching sea traffic from?
AIS uses a distributed TDMA algorithm to assign transmission slots to ships on two different frequencies. This implicitly assumes a limited range of transmission, so the ISS will potentially see several ships transmitting in the same timeslot from widely space ships on the ocean. I don't think this resolves itself by random re-assignment in subsequent transmissions either. It will be interesting to see how successful this is in practice.
There are several websites that show at least coastal traffic of all AIS equipped vessels. I like http://www.marinetraffic.com/ais/
He is gonna be HUGE.
Here's the map of existing coverage. 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.
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
Insert obligatory foil hat quip here.
http://www.orbcomm.com/ais/ais.htm
I welcome the new AIS overlords.. Booty here I come!
just turn the antenna's on their side if the horizontal range is so crappy?!
This completely screws up my plans to grow cannabis on my yacht...
Anyone knows what are the advantages of using ISS for this kind of test? I would be interested to see what it costs to send such an antenna up with the shuttle, test that it does not interfere with the rest of the station and train an astronaut to fix it to the exterior, versus just slapping it as secondary payload on some other satellite or even some dedicated micro-satellite that is piggybacking on the launch of a bigger one.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
How can this technology be leveraged to keep my children safe?
So is this going to be used to find the best spot to crash ISS 2 years after it is completed, just in the unlikely chance that large parts reach the ground?
It's so cute the way folks think this is some new capability. "National assets" FTW.
The ISS operates at a relatively low orbit, even for LEO... for example the Iridium constellation is about twice the ISS' altitude (760km vs 350km). They'd have to find a mission that's within the 400km range of the system, and that has room and power to spare.
That should let them avoid incoming superfreighters... Whait, do we have them on space?
Well I think we've seen by now that the astronauts aboard the ISS would be cool with it.
There are several other spacecraft that have come long before this ISS experiment that proved the concept of AIS from space; Canada has had one up for a while, several US satellites including ORBCOM provide this capability (for a fee) as well as the experimental payload on TacSat-2. Many papers have been written and presented at conferences such as the 4S Conference as well as the Utah State/AIAA Small Satellite Conference...
Cool ... use it to predict the next financial crash.
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This is really cool -- Ham radio has been doing almost exactly this for years.
A ground station with nothing more than a 5 Watt handheld VHF transmitter and a regular 19" long antenna can send a position report and message via a number of satellites, including the International Space Station, using a protocol called APRS. As these are low-earth orbit satellites, you generally only have a few minutes window with each pass, but it's not terribly hard to do and there are a few satellites to potentially catch position data even if you don't get every pass.
Yeah, I've played with a GPS unit hooked up to my 2 meter mobile rig doing just that. It's cool, although in the end I decided it didn't really do enough for me to justify the hassle since it's sort of a kludge on the IC-2200H.
KJ6BSO
This ain't rocket surgery.