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French aircraft carrier Charles de Gaulle tracked via Strava activity in OPSEC failure
(securityaffairs.com)
This is a most excellent place for technology news and articles.
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.
It kind of sounds like you're saying that. Anyways, there's a reason submarines exist