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Re:Earth and Sun by bitpow on Friday October 18, 2019 @05:40PM (#21295311)
What a beautiful, well designed and informative explanation of the complex earth / sun relationship. Well done!

One thing I would love to see is the path of the sun across the sky for different times of year, and different locations on earth.

Here in Seattle, the difference is fairly dramatic between winter and summer, and I've come to realize that the sun is never directly overhead, not even in summer. It would be interesting to see the difference between polar regions vs in the tropics also.

Re:Earth and Sun by saberdancer on Friday October 18, 2019 @06:08PM (#21295455)
Perhaps you are aware, but it is very simple to calculate.

(90-your latitude) + tilt of the earth (23.5 degrees) = maximum height of the sun during the year

(90-your latitude) - tilt of the earth (23.5 degrees) = minimum height of the sun during the year.

Effectively this means if your latitude is 23.5 or less, you get the sun directly overhead at some time during the year. If your latitude is above 67.5, you get polar night as the sun doesn't rise above the horizon (short one at 67.5, but as you go further toward the pole ever longer)

For Seattle, (90-47)+23.5=66.5 maximum. (90-47)-23.5=19.5 minimum.

Re:Earth and Sun by thaumasiotes on Friday October 18, 2019 @07:49PM (#21295927)
Calling these the "maximum height" and the "minimum height" of the sun during the year makes it sound like the height of the sun will always lie between those two figures. That can't be the case -- they have night in the tropics too. Are these what I might call the "high maximum height", the yearly maximum of the maximum height of the sun on any given day, and the "low maximum height", the yearly minimum of the daily maximum height of the sun?
Re:Earth and Sun by TheSpiceIsLife on Friday October 18, 2019 @10:47PM (#21296478)
It’s the minimum and maximum angle between sun and horizon at midday on the solstices.
Re:Earth and Sun by saberdancer on Tuesday October 22, 2019 @02:42AM (#21320931)
Yes, you are correct. My phrasing was unclear, especially in terms of "minimum".

The numbers are for the highest angle of Sun toward the horizon in a single day. This happens at solar noon (solar noon is the moment that Sun passes your local meridian/north south line).

Re:Earth and Sun by a_t48 on Friday October 18, 2019 @10:00PM (#21296355)
Maybe minimum and maximum daily peak?
Re:Earth and Sun by elliottkember on Friday October 18, 2019 @07:49PM (#21295928)
At my school we had this weird climbing frame called the "Pipehenge". I climbed on it for years before we eventually did a class on it and learned that it was an astronomic map: https://www.youtube.com/watch?v=BM4d02tjTqk
Re:Earth and Sun by Tepix on Wednesday October 23, 2019 @01:59PM (#21337119)
Looks they are no longer made, or are they?
Re:Earth and Sun by TheSpiceIsLife on Friday October 18, 2019 @11:05PM (#21296536)
I’d love to make one of those
Re:Earth and Sun by haberman on Friday October 18, 2019 @05:52PM (#21295369)
Very much agreed. Things get weirder and weirder as you get towards the poles. At the poles themselves the sun spends half the year hidden, and the other half spiraling up and then down! But never gets very high above the horizon.

I've been thinking a lot about this lately and was thinking of making some educational YouTube videos about it!

Re:Earth and Sun by TheSpiceIsLife on Friday October 18, 2019 @11:00PM (#21296514)
If you haven’t looked at that sort of thing on YouTube, don’t. Make your own videos first.
Re:Earth and Sun by zargon on Friday October 18, 2019 @08:08PM (#21295991)
SunCalc (http://suncalc.net) has a visualization for sun position throughout the year and time of day. Another great app is Sun Surveyor for Android, which gives an augmented reality view of the sun's position and trajectory.
Re:Earth and Sun by gattr on Saturday October 19, 2019 @03:02AM (#21297239)
The free, cross-platform program Stellarium [0] will show that (among other things).

[0] http://stellarium.org/

Re:Earth and Sun by bostonpete on Friday October 18, 2019 @09:25PM (#21296257)
> I've come to realize that the sun is never directly overhead, not even in summer

It's only ever directly overhead in the tropics.

Re:Earth and Sun by emmelaich on Friday October 18, 2019 @10:24PM (#21296416)
.. which is defined to be between the tropic of cancer and tropic of capricorn; 23°26′12.2″ north and south of the equator respectively.
Re:Earth and Sun by TheSpiceIsLife on Friday October 18, 2019 @11:02PM (#21296526)
Which is because the earths axial tilt is that angle:

Earth's mean obliquity is currently 23°26′12.2″ (or 23.43672°) and decreasing.

https://en.wikipedia.org/wiki/Axial_tilt