The sun dial worked during daylight, but how did people agree on what time it was at night before clocks were invented?

  • @dhork
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    693 months ago

    The stars have a very predictable pattern to them, ancient people had nothing better to do at night than look up, and since there was no light pollution it was quite a show.

    Depending on the time of year, some constellations would be visible all night and move across the sky. That’s where the original Zodiac signs came from.

    • Admiral Patrick
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      3 months ago

      This past winter, I started using Orion as a clock while I was out walking the dogs in the evenings. Got pretty good and could guesstimate the time to within about 30 minutes.

      That only works until about 3 am or so, but if I was out more often that late, I could probably just pick a different constellation.

      • @felbane
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        483 months ago

        Look at this fancy mf able to see Orion at night without it being blocked out by ludicrous amounts of light pollution

        • FaceDeer
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          193 months ago

          Things should get better when Betelgeuse goes supernova.

          • @PunnyName
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            103 months ago

            That fucker needs to hurry

      • @frostysauce
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        53 months ago

        How long do you spend walking your dogs!? Just look at the clock when you go out and won’t you still be accurate to within 30 minutes when you get back?

        • Admiral Patrick
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          3 months ago

          Ha, I phrased it poorly.

          What I meant was that I started noticing Orion’s position in the sky at certain relatively fixed times. After a while, I could just look at where it was, relative to the horizon, and determine the current time within about 30 minutes (between about 5:30 PM and 3 AM when it’s above the horizon here)

      • @[email protected]
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        23 months ago

        could guesstimate the time to within about 30 minutes.

        Which is more than precise enough for the people in the time OP is asking about.

    • @AbouBenAdhem
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      183 months ago

      It’s actually easier to tell the time using the stars rather than the sun, because the elevation of the sun is hard to estimate without using a device like a sundial; but there are always stars near enough to the horizon that their elevation can be estimated with the unaided eye.

      • @[email protected]
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        33 months ago

        Wouldn’t I have to know where stars usually are in order to know the time at night? With the sun all I need is to know which is west vs east.

        • @dustyData
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          133 months ago

          In theory, yes. In practice, you only have to watch the first night, pick a recognizable star pattern. Follow it across the sky during the night and from then on you can use that first read as your reference. Specific stars, their names or whatever is irrelevant as long as you can find the same group of stars every night. Without light pollution it is trivially easier as far more stars are visible and constellations are obvious.

        • @[email protected]
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          3 months ago

          Without light pollution most people can identify the stars with a few nights practice.

          • @[email protected]
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            33 months ago

            Things like Orion and Ursa Major are dead easy. Cassiopeia isn’t hard either. And then with less light pollution you have Andromeda and such.