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The world I’m writing atm has a planet whose sun is described as being permanently moved above its North Pole. Because of a lack of technology (and interest) in outer space, they wouldn’t have a definitive answer in universe anyway, so I’m not hugely concerned with the feasibility of the planet itself. I am open to explanations that involve the central star itself being smaller/closer to the planet, and/or the atmosphere being abnormal.

But there’s my question; what would the weather be like on a planet that has the sun in one place at all times? Bc the planet itself still rotates as normal, and its moon is completely unchanged, would it be considered a tidally locked planet? The planet doesn’t have noticeable seasons (unless the weather could do that on its own? Idk man I kept zoning out in science class when they talked abt the weather, I only cared about the space stuff 😅)

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  • $\begingroup$ Yes, in spades, really big spades too .. "I’m not hugely concerned with the feasibility" Oh it's feasible all right, called Tidal locking, it gives you an Eyeball planet and the weather is going to be awful, like really awful, arctic on the night side blistering desert on the day side and constant strong winds across the surface from the night side to the days side .. oh, and your "pole" won't be the pole, north or south, but they can call it that if they like, they'd just be wrong, but they don't have to know that. $\endgroup$
    – Pelinore
    Commented May 6 at 21:58
  • $\begingroup$ Here you might find that helpful, or not, might be worth a read though. $\endgroup$
    – Pelinore
    Commented May 6 at 22:14
  • $\begingroup$ And this answer to a similar question may have the answers you're looking for "There are atmospheric models for tide-locked worlds that show a permanent cyclone on the light side, with constant winds blowing between hot and cold sides" $\endgroup$
    – Pelinore
    Commented May 6 at 22:51
  • $\begingroup$ As others have said it would be a tidally locked planet for real world examples, but I think what you are suggesting is a non-real example where instead of planet spinning on vertical axis at same rotation as sun you are suggesting it spins the other way on horizontal axis (thus making E/W the new N/S). It's very unlikely to occur but it might not be impossible to ever occur (imagine some giant clamps stuck on Earth at the poles and then spun around on a vertical axis (can be done extremely slowly to not kill all life on Earth). Weather wise it might be similar to tidally locked planets? $\endgroup$
    – HSharp
    Commented May 7 at 14:32

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sun is described as being permanently moved above its North Pole.

what you are describing is physically impossible.

It is possible to have the sun fixed at a position in the sky. Those who have studied call this configuration tidal locking. It happens when the planet takes the same time to revolve around its axis and to orbit around its sun.

But this means that the geographical poles are always at the terminator, which is the line diving the day zone from the night zone.

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    $\begingroup$ Is it impossible or improbable? Uranus axial tilt is at nearly a 90 deg and actually revolves in a retrograde direction, presumably after a great collision in the distant past. If Uranus were much closer to the sun, could it not have become tidally locked at one of the poles to the sun? Or would gyroscopic forces prevent this? $\endgroup$
    – Gillgamesh
    Commented May 6 at 18:31
  • $\begingroup$ @Gillgamesh if the pole always look toward the star, it cannot be pole, as it will be rotating while the planet orbits $\endgroup$
    – L.Dutch ♦
    Commented May 6 at 18:43
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    $\begingroup$ Spinning on one axis very fast, and on another axis very slowly (so as to be tidally locked as you descrive), is indeed physically impossible. Here's a good answer on another question with links to yet more info: worldbuilding.stackexchange.com/a/156388/561 $\endgroup$
    – talrnu
    Commented May 6 at 19:30
  • $\begingroup$ They (the natives) can call it the pole if they want, but it won't be what we'd call the pole. $\endgroup$
    – Pelinore
    Commented May 6 at 21:56
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Not quite what you're describing, but a tidally locked planet rotates at the same rate it orbits its star, so the sun never moves in the sky.

Such a planet would definitely have weather, and it would probably be quite extreme. Temperature differences between the extremely warm lit side and the extremely cold dark side would cause the atmosphere to circulate across the twilight boundary between them. This circulation gives rise to weather patterns as it moves moisture and air of different temperature/pressure about. The weather is probably extreme because the temperature differences would be so extreme: constant direct sunlight roasts one side probably hundreds of degrees higher than the perpetual frigid darkness on the other.

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