Earlier quoted context omitted.
But the ocean is very very huge to find it still.
And American carriers never operate alone, it's a whole Carrier Battle Group there.
The battle group doesn't cruise around in formation, for specifically this reason.
France's aircraft carrier located in real time by Le Monde through fitness app
171–180 of 571 posts
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#172Re: France's aircraft carrier located in real time by Le Monde through fitness app
#173How does the smart watch have any service out in the middle of the Med? Must be getting it from the ship, are they not firewalling outbound traffic?
GPS watches don't need service, they just need line of site to the GPS satellites. Uploading to Strava requires service, but that can be done any time after the activity.
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#174How does the smart watch have any service out in the middle of the Med? Must be getting it from the ship, are they not firewalling outbound traffic?
GPS tries to cover the whole globe, app uses GPS to get location. Ship probably has internet connection in the from of wifi or a cell tower with a starlink or other sattelite backbone link and app's traffic is encrypted so ships firewalls cannot easily block this
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#175How does the smart watch have any service out in the middle of the Med? Must be getting it from the ship, are they not firewalling outbound traffic?
Under wartime conditions they would but rules are looser out of combat so sailors can use personal devices for entertainment etc to keep morale up.
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#176Re: France's aircraft carrier located in real time by Le Monde through fitness app
#177Earlier quoted context omitted.
Those suffer from the same problem. There's a lot of ocean, and if you don't know where to look then you won't find what you're looking for.
Eh, not really. Synthetic Aperture Radar satellites used for marine ship detection have extremely wide sensor swath widths, and ships show up as very bright radar targets against the ocean. Detecting a large ship, even in a very large search area, is almost trivial. Identifying a ship is harder, but not insurmountable. In particular, large ships like aircraft carriers tend to have very identifiable radar signatures i…
How do these work? I would think radar would have a very difficult time seeing a ship against the backdrop of the ocean from so high above. Is the satellite bouncing radar waves off the side of the ship as the satellite is near the horizon? Even if you can detect a ship, I'm having a hard time imagining a sufficiently high radar resolution for such a wide sensor swath width at such an extreme range. Is the idea that you locate it with the wide sensor swath and then get a detailed radar signature from a more precise sensor?
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#178Earlier quoted context omitted.
This capability is available only to few countries on planet. Not all of them.
You can rent access to nearly real-time custom satellite targeting for <$3k per image. That means while you're correct that not all countries can afford it, most can.
So you task the satellite to where you know the ship is?
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#179Earlier quoted context omitted.
I really don’t want to work for the defense industry, but I have to admit that they do have very fun problems to solve. You know there are people at NRO who are dedicated to ship tracking via satellite. I assume they can easily track ships without cloud cover, but how do they do it when it’s cloudy? Heat signatures? Synthetic Aperture Radar? Wake detection?
I'd be mildly surprised if they not using SAR for this all the time, not only during cloud cover. The Soviet Union was using radar satellites (the RORSATs) to track carriers decades ago.
Neither SAR nor high resolution optical sensing are trivial at panopticon scale.
https://www.youtube.com/watch?v=-GTpBMPjjFc is a good overview of what's up there so far, and what's coming as they really try to scale the technology.
Bandwidth and processing are substantial bottlenecks with SAR; Only targeted and stationary applications have been broadly useful so far, and more focus has been put on planes than satellites for this. SAR is not as simple as taking a static image with a fixed resolution, your sensing window has got a target velocity and distance in mind and the antenna and processing needs to be tuned for that.
I would think that medium and high orbit optical tracking (daytime, cloudless sky) is probably used, because with video you can reasonably track subpixel targets if they're high contrast, without a lot of data transmission requirements.
Re: France's aircraft carrier located in real time by Le Monde through fitness app
#180It would be cool if they actually wer just altering the GPS location data before uploading, so the location reported was false. GPX/TCX files are trivial to edit. "All warfare is based on deception"