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

  • AbouBenAdhem@lemmy.world
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    9 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.

    • Thief_of_Crows@lemmy.ml
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      9 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@lemmy.world
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        9 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.

        • Flax@feddit.uk
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          9 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.