The moiré effect lights that guide ships home
Tom Scott1 HN recommender · recommended in 1 month, 2024–2026
explainer · general · evergreen · 2024–2026 on HN
Tom Scott investigates moire-effect beacons, called Inogon leading marks, a Swedish invention from the 1980s that shows different patterns depending on the viewer's position. He visits one used to mark an undersea cable and tracks down its history.
Linked as the accessible explanation of how moire navigation lights work.
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3 comments from Hacker News
You might also find moiré-effect navigation beacons interesting, like the one that Tom Scott visits here: ▶ this video
It is used and I guess it works largely the same way as in author’s first picture: you get arrows pointing towards where you should correct your course to. Tom Scott has made a video on those: ▶ this video
This is nothing but blogspam of the embedded Tom Scott video: ▶ this video . This article adds nothing that is not already included in the video itself.