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>>Sun wise, situations are a pretty different at any moment in the two countries The sun is still at its high point at the same time of the day in both countri

>>Sun wise, situations are a pretty different at any moment in the two countries The sun is still at its high point at the same time of the day in both countries

makeitdouble 3y ago
Doesn't that presume the earth is perfectly turning around its North/South axis ?
- mixmastamyk 3y ago
  How would a rock spin other than "perfectly?"
  - makeitdouble 3y ago
    It was more about the spin axis: timezones are vertically cut on a South/North line, while the earth rotation deviates from there. I actually couldn't find how much it deviates. I assume there's variation depending on the seasons as well.
    - mixmastamyk 3y ago
      Not really, there’s a tiny bit of wobble but it moves over a thousands years or so, nothing to worry about. The axis doesn't change to my knowledge. https://en.m.wikipedia.org/wiki/Axial_precession https://en.m.wikipedia.org/wiki/Axial_precession Magnetic poles changing is not relevant it seems.
      - makeitdouble 3y ago
        Thanks, that I didn't know. I'm kinda glad I tried to explain this, because I realize just how much I lack the proper words for it. The earth rotation wobbles a bit, but the axis itself is also not tilted towards the sun (it has no specific reason to) nor tilted towards the inside of the revolution axis relative to the sun. Basically the earth can be spinning on itself around any axis (let's call it A), while revolving around the sun on an unrelated axis (B). And neither A nor B has to be following the North/South axis. That's where the idea that a latitudinal timezone sees a similar solar cycle seems at odds to me. If an image can help more, the earth's self rotation and sun revolution in this video are clearly not aligned, nor any of them follow the North/South axis: https://www.britannica.com/video/151528/Earth-rotation-axis-revolution-Sun https://www.britannica.com/video/151528/Earth-rotation-axis-...
        mixmastamyk 3y ago
        Right they aren’t aligned. Sun’s axis is aligned perpendicular to the ecliptic. Earth is tilted 23.5 degrees from that. So North pole is tilted towards the sun on June 21 and South pole tilted towards it on December 21—why there are seasons. Doesn’t affect timezones to my knowledge.
brightlancer 3y ago
> The sun is still at its high point at the same time of the day in both countries No. Helsinki's solar noon is about 35 minutes later than Cape Town's and 100 minutes later than Pretoria's. This is normal, because time zones are mostly broken into non-uniform 1 hour increments across 180 degrees of latitude.
- garrickvanburen 3y ago
  yep - timezones are not straight lines - namely around the international date line.

>>Sun wise, situations are a pretty different at any moment in the two countries The sun is still at its high point at the same time of the day in both countries

makeitdouble 3y ago

Doesn't that presume the earth is perfectly turning around its North/South axis ?

mixmastamyk 3y ago
How would a rock spin other than "perfectly?"
- makeitdouble 3y ago
  It was more about the spin axis: timezones are vertically cut on a South/North line, while the earth rotation deviates from there. I actually couldn't find how much it deviates. I assume there's variation depending on the seasons as well.
  - mixmastamyk 3y ago
    Not really, there’s a tiny bit of wobble but it moves over a thousands years or so, nothing to worry about. The axis doesn't change to my knowledge. https://en.m.wikipedia.org/wiki/Axial_precession https://en.m.wikipedia.org/wiki/Axial_precession Magnetic poles changing is not relevant it seems.
    - makeitdouble 3y ago
      Thanks, that I didn't know. I'm kinda glad I tried to explain this, because I realize just how much I lack the proper words for it. The earth rotation wobbles a bit, but the axis itself is also not tilted towards the sun (it has no specific reason to) nor tilted towards the inside of the revolution axis relative to the sun. Basically the earth can be spinning on itself around any axis (let's call it A), while revolving around the sun on an unrelated axis (B). And neither A nor B has to be following the North/South axis. That's where the idea that a latitudinal timezone sees a similar solar cycle seems at odds to me. If an image can help more, the earth's self rotation and sun revolution in this video are clearly not aligned, nor any of them follow the North/South axis: https://www.britannica.com/video/151528/Earth-rotation-axis-revolution-Sun https://www.britannica.com/video/151528/Earth-rotation-axis-...
      - mixmastamyk 3y ago
        Right they aren’t aligned. Sun’s axis is aligned perpendicular to the ecliptic. Earth is tilted 23.5 degrees from that. So North pole is tilted towards the sun on June 21 and South pole tilted towards it on December 21—why there are seasons. Doesn’t affect timezones to my knowledge.

brightlancer 3y ago

> The sun is still at its high point at the same time of the day in both countries No. Helsinki's solar noon is about 35 minutes later than Cape Town's and 100 minutes later than Pretoria's. This is normal, because time zones are mostly broken into non-uniform 1 hour increments across 180 degrees of latitude.

garrickvanburen 3y ago
yep - timezones are not straight lines - namely around the international date line.