01 December 2020

The changing location of sunrise/sunset


As an adult I'm surprised how many people are unaware of this phenomenon, but TBH when I was a teenage driver I remember my disappointment that the Minnesota highway department had positioned a road so that I had to drive directly into the sunset on my way home from work...

The phenomenon is discussed briefly at APOD and at EarthSky.  Image via.

18 comments:

  1. not securely anchoredDecember 1, 2020 at 1:49 PM

    Yes, I put up a curtain to stop the evening sun in the summer; remove it in the winter.

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    1. WatsonScienceDecember 1, 2020 at 4:13 PM

      We do the same. Our home's front door and living room windows are almost directly facing the summer afternoon sun and sunset. We hang more opaque curtains inside and a bamboo curtain on the front porch to block the summer sun and keep the house cooler. We usually are able to take them down around the time daylight savings time ends.

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  2. delagarDecember 1, 2020 at 2:24 PM

    It was the sun directly into my eyes as I drove to work one winter that first alerted me to this phenomenon!

    A month or so later, though I was still going to work at the same time, the sun was no longer blinding me at the main stoplight.

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  3. ChristopherDecember 1, 2020 at 2:33 PM

    Growing up my bedroom had a west-facing window and it was fascinating to me to see that the sun didn't really set in the west but actually moved. When I saw a photograph illustrating an analemma it made perfect sense.
    And I sympathize with the frustration of driving into the sun. I used to ride the bus home from work and felt bad for the drivers who'd be blinded by the afternoon glare around this time of year.

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  4. Heather MadroneDecember 1, 2020 at 2:39 PM

    We had friends who spent a year marking the position of the noon sun on their dance room floor. They used this to paint a beautiful analemma on that floor.

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  5. UnknownDecember 1, 2020 at 3:24 PM

    My windows face east, and I love to watch the progression of the sunrise along the horizon. I should try to take a series of photos like this.

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  6. AnonymousDecember 1, 2020 at 3:34 PM

    The moon too, is rising and setting pretty far north these days.

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  7. rockyDecember 1, 2020 at 4:33 PM

    My house is in an area where everything is aligned to the geography rather than NSEW and it's pretty far north. At the summer solstice the sun rises in what "feels like" the NNE and sets in the WNW. And I never know how to give directions.

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  8. northern viewDecember 1, 2020 at 10:31 PM

    I am at 64 degrees latitude. At the summer solstice, about 30 hours of direct sun, the sun rises in the north east- and sets in the north west- both visible out the north windows. At winter solstice,an hour and a half of direct sun, the sun rise and sun set are both nearly due south- visible out the south windows.
    its pretty amazing.

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    1. AnonymousDecember 2, 2020 at 11:38 AM

      living at 41N and traveling to 45N in winter, i notice the lower height the sun reaches at 45N versus at home.

      in winter, the sunrise shines at the head of my bed and in the summer, the sunrise shines at the foot of my bed.

      I-)

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    2. AnonymousDecember 3, 2020 at 11:33 AM

      the reason why i notice the sun so low at 45N in winter is that the sun is so low in the sky that it is in my field of vision. in winter, at 41N, the sun is still up high enough not be in my general view.

      I-)

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    3. northern viewDecember 6, 2020 at 3:04 PM

      oops that should read "at the summer solstice, about 20 hours of direct sun"... apologies.

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  9. Marlys Hesch SebaskyDecember 2, 2020 at 9:08 AM

    Lesson learned: Try to live east of where you work.

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  10. Zak GriefenDecember 2, 2020 at 11:43 PM

    http://solar-center.stanford.edu/art/analemma.html

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  11. JimDecember 3, 2020 at 12:44 AM

    Recently, I was wondering how the sun would move in the sky on the equinox at the south and north pole. I know that at the height of summer it circles the horizon and in winter there is no sun, but what about the equinox. The answer turned out to be more bizarre than expected. On the spring equinox the sun rises above the horizon for the first time all winter and that it doesn't set again until the following autumn equinox. Literally 6 months of day and 6 months of night.

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  12. giadaDecember 4, 2020 at 11:31 PM

    The original city grid for Los Angeles created by the Spanish was based on The Laws of the Indies, which decreed the streets be laid out at a 45 degree angle off the North/South compass points. It ended up a little off from that. You can see where the city started building up around it because they switched to the Jeffersonian squares. Jefferson may have had some good ideas but this definitely was not one of them. I've had more than one commute with the sun in my eyes both ways.

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  13. UnknownDecember 5, 2020 at 7:23 PM

    Thanks for posting this! I used it in the precalculus class I teach as an example of how we see sinusoidal functions in the natural world (we were going over transformations of trig functions). The kids thought it was super cool. Next class we'll close with fitting a sine function to it.

    I love this blog, thanks for doing what you do!

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    1. MinnesotastanDecember 5, 2020 at 7:48 PM

      Sounds like an interesting class.

      This is not the same thing, but if you want to tantalize them with "seeing" sine waves, show them this optical illusion:

      https://tywkiwdbi.blogspot.com/2017/12/all-horizontal-lines-are-identical.html

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