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Comment by cghendrix | Hacker News Reader

Wonder how the data for the actual position of the ship is obtained or if it’s estimated and just hard coded on to the map?

I always love sites that are question in the domain with answers in the webpage as the main content.

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VesselFinder and MarineTraffic use the data broadcast by vessels on AIS[0]. The AIS devices can be programmed with the dimensions of the vessel, location of the AIS GPS antenna relative to the vessel (ie, is it right aft, or in the middle, etcetera), and uses sensor data from the network bus to get direction, speed and the like. So yeah, if the ship's AIS is saying "I'm at latitude, longitude doing 0 knots, last reported course was 73 degrees", the websites can generate a somewhat accurate picture.

0: https://en.wikipedia.org/wiki/Automatic_identification_syste...

This is one particular outlet[1] for that data but, AFAIK, all modern commercial vessels continuously report their location via satellite or, preferably, coastal AIS. That data is collected by something then APIs happen along with aggregation and probably more APIs and... after all that, the data is pretty widely available.

Ship location isn't considered privileged security information which was a bit surprising to me since pirates are still a thing, but yea - that's the state of the world.

Edit: Apparently I forgot to include the link, here it is:

1. https://www.marinetraffic.com/en/ais/home/centerx:32.5/cente...

As a small vessel (10 metres) owner and operator, it's quite nice that AIS operates over VHF. I can install an AIS receiver and see precisely what's coming my way, and the instrumentation available to me can predict whether I might collide with the ship, or if I'll pass ahead/behind (I prefer behind). Useful in the dark when distance is hard to gauge.

Saw on twitter the other day that one vessel going past the east coast of Africa had changed their info field (destination I think) to "ARMED GUARD ONBOARD"..

Twitter link:

https://twitter.com/lemonodor/status/1374803809696817154

It's super useful to know the location, speed and course of other vessels nearby for navigational purposes. For those few regions where piracy is a serious issue, vessels are either escorted by navy ships in convoys, arrange private security contractors or turn off AIS. The benefits of hiding yourself don't outweigh the downsides though, especially not in "civilized" oceans.

> isn’t considered privileged information

Not only that, but Bloomberg terminals have the ship locations in real time because it impacts trading a lot: Petrol, ore, cereals, etc.

You can see it here: https://www.vesselfinder.com/?imo=9811000

Yes. I notice that the two Maersk freighters behind the Ever Given are no longer there. It looks like all traffic has been cleared from the canal on both sides. Zoom out. The north end of the Gulf of Suez looks like a parking lot. So does the Med north of Port Said. So does Fayed, the lake in the middle of the canal.

Smit, the big Dutch salvage firm, has been called in and already has their first heavy equipment, a dredger, on site. "Days to weeks" is all they'll say. The good case is that they pump fuel and ballast water out of the ship, plus some dredging, and it floats free. The not so good case is they bring in a big crane and start unloading containers. The bad case is that the ship is partly sunk and will have to be patched and refloated. The really bad case is that the hull is so badly damaged that the ship has to be cut apart in place.

Meanwhile, shipping from China to Europe is now US$4000/TEU. Usually it's around US$1000. China's "Belt and Road" rail plan may pay off.

Or the super-extra-bad case: The ship breaks while attempting to pull it free. Pieces of ship + 20000 containers in the canal. How long would it be blocked for. Full-spectrum catastrophe!

How far could it go? Could it go political about Egypt’s management of the crisis?

> China's "Belt and Road" rail plan may pay off.

That’s great conspiracy theory fodder right there. :)

Edit: perhaps it’s not so far fetched, if the boat drew a giant penis before getting stuck.

Removing ballast from a ship with such a heavy top load is super risky. That could turn 'days or weeks' into 'months or years'.

I know very little about boat data but I was also curious; it looks like it is using Vesselfinder which in turn uses data from this AIS system.

https://en.wikipedia.org/wiki/Automatic_identification_syste...

There is as much information as a normal human could want to know about how ship location data is tracked ;-)

On iOS you can use Vessel Finder Pro. It provides a real-time world map of all (for some reasonable definition of all) ships. Most of maps views I have seen of this ship are just screen shots from this app. I paid the $10 just to confirm this fact yesterday as Ship Finder, my old standby, didn’t have it.

https://en.wikipedia.org/wiki/Automatic_identification_syste...

See the "Broadcast information" section.

Position, heading, speed, unique ID, etc. are all broadcast "every 2 to 10 seconds".

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