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A comment on Simple streetlight hack could protect astronomy from urban light pollution. Parent comment

Re:Simple streetlight hack could protect astronomy from urba... by anon_cow1111 on Saturday November 18, 2023 @08:44PM (#38327415)
>Let's look at London. I picked it at random, but it just happens to have a land area around 1500km^2

Um am I really really tired and not reading correctly, or is this confusing linear area with square area? London doesn't stretch from New york to Florida.

186000 miles/second * pulse of .003 = 558 miles ~= 900 km

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Re:Simple streetlight hack could protect astronomy from urba... by calamari4065 on Sunday November 19, 2023 @06:13PM (#38339622)
I knew I fucked something up. Don't do math while smoking, kids.

Either way, propagation delay is a huge problem with synchronizing systems. It's not something you usually think about

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Re:Simple streetlight hack could protect astronomy from urba... by sand500 on Monday November 20, 2023 @02:11PM (#38352893)
Dont you have propagation delay in reverse too? Let's say you do turn off all the lights at the exact same time. The light hitting the telescope also travels at the speed of light.
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