The moiré effect lights that guide ships home

Tom Scott · 3.1M views · 2018-03-05 · 3:54

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Overview

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.

On Hacker News

Linked as the accessible explanation of how moire navigation lights work.

Recommended by 1 HN people across 1 months · HN mentions 2024–2026

Topics

Ships, submarines & maritime Everyday physics & science demos

What people said

wgrover · 2024-02 · Recommendation
You might also find moiré-effect navigation beacons interesting, like the one that Tom Scott visits here: [VIDEO]
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notpushkin · 2026-08 · Reference
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: [VIDEO]
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dublinben · 2024-09 · Reference
This is nothing but blogspam of the embedded Tom Scott video: [VIDEO] . This article adds nothing that is not already included in the video itself.
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Sources

Video by Tom Scott, played through YouTube.

HN Library · Source license

Data and selection notes

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