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My neighbor's laser pointer showed me the curve last Tuesday

He aimed a green laser across the lake at 7pm and the dot was clearly above the shoreline by 3 feet. Has anyone else tried this with a visible beam at night?
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3 Comments
ben_lewis
ben_lewis17d ago
I tried this same thing last summer on Lake Michigan near Grand Haven with a 5mw red laser. The dot was about 2 feet above the water line at about half a mile out, and the beam itself looked like it was bending up slightly as it went. I used a phone camera on a tripod to get a video of it, and you could see the curve pretty clearly when I played it back. It's one of those experiments that just works better than you'd expect with a clear night and calm water.
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laura_chen41
Wait you actually got a video of the beam bending upward? That's wild because I always thought that effect was mostly theoretical or only visible in perfect conditions. I need to see that footage because half a mile out with a cheap 5mw laser sounds impossible to me.
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emery290
emery29016d ago
My buddy Darren and I tried this on the Great Salt Lake a few years back with a 10mw green laser and it worked way too well. The salt flats around there are so flat and still at night that the beam looked like it was curving up like a rainbow almost. We were only about a quarter mile out and could see the dot drift up like 6 inches over the water.
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