• sudo42@lemmy.world
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    3 months ago

    So can someone who is more familiar with this subject answer, “Are these pictures taken at the same time of day with or without seasonal adjustments to time (Daylight Savings Time, etc.)?”

    I understand why the sun would move vertically over the year due to the tilt of the Earth, but what causes the horizontal movement?

    • Balinares@pawb.social
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      3 months ago

      The Earth’s orbit is an ellipse, not a circle, and therefore the Earth speeds up or slows down depending on where on its orbit it is at the time. In turn this means that the duration of the solar day fluctuates from day to day, from a bit under 24h to a bit over 24h and back.

      So if you take a picture every 24h precisely the sun will appear to move horizontally a little bit on top of the expected vertical movement.

      • sudo42@lemmy.world
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        3 months ago

        The Earth’s orbit is an ellipse, not a circle, and therefore the Earth speeds up or slows down depending on where on its orbit it is at the time

        That’s it! Thank you.