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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.
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.