{"page":"<link rel=\"stylesheet\" href=\"https://lessonplanet.com/assets/packs/css/resources-572d6a42.css\" />\n<link rel=\"stylesheet\" href=\"https://lessonplanet.com/assets/packs/css/lp_boclips_stylesheets-f4d0de30.css\" media=\"all\" />\n<div data-title='The Moiré Effect Lights That Guide Ships Home' data-url='/boclips/videos/5cdef9026f3fe04e7bc6c57c' data-video-url='/boclips/videos/5cdef9026f3fe04e7bc6c57c' id='bo_player_modal'>\n<div class='boclips-resource-page modal-dialog panel-container'>\n<div class='react-notifications-root'></div>\n<div class='rp-header'>\n<div class='rp-type'>\n<i aria-hidden='true' class='fai fa-regular fa-circle-play'></i>\nVideo\n</div>\n<h1 class='rp-title' id='video-title'>\nThe Moiré Effect Lights That Guide Ships Home\n</h1>\n<div class='rp-actions'>\n<div class='mr-1'>\n<a class=\"btn btn-success\" data-posthog-event=\"Signup: LP Signup Activity\" data-posthog-location=\"body_link_boclips\" data-remote=\"true\" href=\"/subscription/new\"><span><span>Get Free Access</span><span class=\"\"> for 10 Days</span><span>!</span></span></a>\n</div>\n</div>\n</div>\n<div class='rp-body'>\n<div class='rp-info'>\n<div aria-label='Hide resource details' class='rp-hide-info' role='button' tabindex='0'>&times;</div>\n<i aria-label='Expand resource details' class='rp-expand-info fai fa-solid fa-up-right-and-down-left-from-center' role='button' tabindex='0'></i>\n<i aria-label='Compress resource details' class='rp-compress-info fai fa-solid fa-down-left-and-up-right-to-center' role='button' tabindex='0'></i>\n<div class='rp-rating'>\n<span class='resource-pool'>\n<span class='pool-label'>Publisher:</span>\n<span class='pool-name'>\n<span class='text'><a data-publisher-id=\"470201\" href=\"/search?publisher_ids%5B%5D=470201\">Tom Scott</a></span>\n</span>\n</span>\n</div>\n<div class='rp-description'>\n<span class='short-description'>I'd never heard of moiré effect beacons until I got an email asking me about them. It seemed like a really clever idea - but it was really hard to research. Or at least it was, until I stumbled upon one magic phrase that revealed its...</span>\n<span class='full-description hide'>I'd never heard of moiré effect beacons until I got an email asking me about them. It seemed like a really clever idea - but it was really hard to research. Or at least it was, until I stumbled upon one magic phrase that revealed its history. It turns out this thing's called an \"Inogon leading mark\" or \"Inogon light\" -- Inogon, not Inogen -- and it's a Swedish invention from the 1980s. But there's still a question: why is being used to mark an undersea cable, instead of guiding people home? (Full disclosure: there were some weird strobing effects from the light that only showed up when I got the footage into the edit, so the image you see here has been digitally stabilised so it appears the same way on screen as it does in person!) Thanks to Andrew Stine for suggesting this! References: The original Wikipedia <a href='https://en.wikipedia.org/wiki/Moir%C3%A9_pattern' target='_blank' rel='nofollow'>article</a> The <a href='https://patents.google.com/patent/US4629325' target='_blank' rel='nofollow'>patent</a> The US military analysis [<a href='http://www.dtic.mil/dtic/tr/fulltext/u2/a168108.pdf' target='_blank' rel='nofollow'>PDF]</a> I'm <a href='http://tomscott.com' target='_blank' rel='nofollow'>at</a> on Twitter <a href='http://twitter.com/tomscott' target='_blank' rel='nofollow'>at</a> on Facebook <a href='http://facebook.com/tomscott' target='_blank' rel='nofollow'>at</a> and on Snapchat and Instagram as tomscottgo</span>\n</div>\n<div class='action-container flex justify-between'>\n<button aria-expanded='false' aria-label='Read more description' class='rp-full-description' type='button'>\n<i class='fai fa-solid fa-align-left'></i>\n<span id='read_more'>Read More</span>\n</button>\n<div class='rp-report'>\n</div>\n</div>\n<div aria-labelledby='resource-details-heading' class='rp-info-section'>\n<h2 class='title' id='resource-details-heading'>Resource Details</h2>\n<div class='rp-resource-details clearfix'>\n<div class='detail'>\n<dl>\n<dt>Curator Rating</dt>\n<dd><span class=\"star-rating\" aria-label=\"4.0 out of 5 stars\" role=\"img\"><i class=\"fa-solid fa-star text-action\" aria-hidden=\"true\"></i><i class=\"fa-solid fa-star text-action\" aria-hidden=\"true\"></i><i class=\"fa-solid fa-star text-action\" aria-hidden=\"true\"></i><i class=\"fa-solid fa-star text-action\" aria-hidden=\"true\"></i><i class=\"fa-regular fa-star text-action\" aria-hidden=\"true\"></i></span></dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt class=\"educator-rating-title\">Educator Rating</dt><dd><div class=\"educator-rating-details\" data-path=\"/educator_ratings/rrp_data?resourceable_id=79453&amp;resourceable_type=Boclips%3A%3AVideoMetadata\"><span class=\"not-yet-rated\">Not yet Rated</span></div></dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt>Grade</dt><dd title=\"Grade\">9th - 11th</dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt>Subjects</dt><dd><span><a href=\"/search?grade_ids%5B%5D=255&amp;grade_ids%5B%5D=256&amp;grade_ids%5B%5D=257&amp;search_tab_id=1&amp;subject_ids%5B%5D=1216220\">All Subjects</a></span></dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt>Media Type</dt><dd><span><a href=\"/search?grade_ids%5B%5D=255&amp;grade_ids%5B%5D=256&amp;grade_ids%5B%5D=257&amp;search_tab_id=2&amp;type_ids%5B%5D=4543647\">Instructional Videos</a></span></dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt>Source:</dt>\n<dd></dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt>Date</dt>\n<dd>2019</dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<i aria-hidden='true' class='fai fa-solid fa-language'></i>\n\n</dl>\n</div>\n<div class='detail'>\n<dl>\n<dt>Audiences</dt><dd><span><a href=\"/search?audience_ids%5B%5D=371079&amp;grade_ids%5B%5D=255&amp;grade_ids%5B%5D=256&amp;grade_ids%5B%5D=257&amp;search_tab_id=1\">For Teacher Use</a></span></dd><dd class=\"text-muted\"><i class=\"fa-solid fa-lock mr5\"></i>2 more...</dd>\n</dl>\n</div>\n<div class='detail'>\n<dl>\n\n</dl>\n</div>\n</div>\n</div>\n<div aria-labelledby='educator-ratings-heading' class='rp-info-section'>\n<h2 class='title sr-only' id='educator-ratings-heading'>Educator Ratings</h2>\n<div id=\"educator-ratings-root\"></div><div id=\"all-educator-ratings-root\"></div><div id=\"educator-rating-form-root\"></div>\n</div>\n</div>\n<div class='rp-resource'>\n<div aria-label='Show resource details' class='rp-show-info' role='button' tabindex='0'>\n<i class='fai fa-solid fa-align-left'></i>\nShow resource details\n</div>\n<div aria-label='Video player' class='player ie' id='player-wrapper' role='region'>\n<div class='relative container mx-auto' id='lp-boclips-visitor-thumbnail'>\n<a class=\"block\" data-html=\"true\" data-placement=\"bottom\" data-trigger=\"click\" data-content=\"<div class=&quot;text-center py-2&quot;><a class=&quot;bold&quot; 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