Comment on French aircraft carrier Charles de Gaulle tracked via Strava activity in OPSEC failure

• astronaut_sloth@mander.xyz ⁨16⁩ ⁨hours⁩ ago

  Sort of. Satellite resources are surprisingly scarce, so a lot are focused where people are, i.e. land. Plus, for the imagery sats that are focused on the ocean, ships are also tiny in a literal ocean of blue. It’s just a spec. While the resolution could be good, have fun looking for that spec. That’s why most countries use signal collection to locate vessels at sea. (I’m over-simplifying a lot, but you get the picture)

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  • FauxLiving@lemmy.world ⁨15⁩ ⁨hours⁩ ago

    While the resolution could be good, have fun looking for that spec.

    Seems like an easy but tedious job. Something that a computer can do.

    Object detection algorithms are incredibly fast and can learn to tell the difference between an aircraft carrier and an ocean.

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    • astronaut_sloth@mander.xyz ⁨14⁩ ⁨hours⁩ ago

      There are a surprising amount of false positives when using object detection on maritime imagery. While a carrier is a spec, there are a ton of specs in the ocean that can look similar enough. Plus, weather has a huge hand to play. If it were always perfectly clear, then it’s an easier problem, but one cloud can really mess up the detection. Ultimately, ship detection is a difficult problem (not intractable but still hard).

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      • FauxLiving@lemmy.world ⁨12⁩ ⁨hours⁩ ago

        False positives are fine, you assign 1, 10, 50, 100 analysts to review hits. You only need to find it once, then the search area becomes incredibly small for each subsequent satellite pass.

        I’m not saying that it is easy, just that you don’t need to have a surface ship within 15 nm in order to see it.

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• UnspecificGravity@piefed.social ⁨13⁩ ⁨hours⁩ ago

  It depends a great deal on if you have access to a real-time satellite feed and know where to look.

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• theneverfox@pawb.social ⁨14⁩ ⁨hours⁩ ago

  It’s the ocean. The majority of Earths surface where there’s usually not much going on

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• Iconoclast@feddit.uk ⁨14⁩ ⁨hours⁩ ago

  You still need to know where to point that spy satellite’s camera at. If you take picture that covers hundreds of square kilometers then you don’t have enough resolution to spot the ship but you can’t zoom in much either because you don’t know where to zoom.

  It’s different with buildings because you know where they are.

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