This is all rampant speculation based on in-game observations, but...
We know Eorzea has seasons, but they're very mild compared to seasons on Earth. Our seasons are caused by the axial tilt of the Earth:
![[Image: 266px-Seasons.svg.png]](https://upload.wikimedia.org/wikipedia/commons/thumb/1/12/Seasons.svg/266px-Seasons.svg.png)
You can see from this diagram that each hemisphere has summer when the sun's rays are closer to being overhead, and winter when they're furthest from it. You can also see why the seasons are swapped between the northern and southern hemispheres - the north has summer when the south has winter, and visa versa.
The tilt is measured from the plane of the Earth's orbit around the sun. You can see that the Earth has a pretty decent tilt, enough to produce a pretty significant difference between summer and winter. If the tilt was greater, you'd see greater differences between the seasons.
Now in Eorzea, on the other hand, we don't see any real distinctions between summer and winter. There's a light snow around Starlight, but *every* place gets that. Other than that, every season seems to be basically the same. Corthas is always cold, Thanalan is always hot, the Shroud is always temperate, and these don't really vary with the seasons. You can assume, then, that Hydaelyn's axial tilt is basically straight up and down, making the angle of Hydaelyn's sun's rays the same for any given spot on the surface all throughout the year.
Now, you can imagine you're sitting on the planet, looking up at the sky. You're able to see a circular portion of the sky that's based on the longitude and latitude of the spot you're sitting at, and what time it is. As the planet spins, your visible circle spins with it, which is what lets you see different stars as the night progresses. Now, there are a couple of things that limit what you can and can't see. One of them is the hours of night. You simply can't see stars (except in extreme circumstances) while the sun is shining. The other is your latitude (which is why the night sky is different in the southern hemisphere). You're seeing, on any day, a strip of sky.
As the year progresses, you can see different constellations, though. This is mainly a phase thing: As the Earth goes around the sun, you're seeing a different portion of the sky during the hours of darkness. The axial tilt of the Earth plays into this, too, because the days are shorter for winter and longer for summer. Longer night means more stars you can see.
Since Hydaelyn's axial tilt is basically nil, the only thing that affects what stars you can see is the phase progression from the planet going around the sun: You can still see a different part of the sky during the night different times of the year. Now, I haven't really studied the sky in depth in Eorzea, but I haven't noticed a seasonal difference in the stars. The only thing we can deduce from this is that there's a strangely coincidental correlation between the length of the day and the year, which means that we're always seeing the same section of sky during the night. That's pretty long odds, but as they say, when you eliminate the impossible, what you have left, however improbable, must be the truth.
But what explains this improbable coincidence? Clearly, the answer is magic.
We know Eorzea has seasons, but they're very mild compared to seasons on Earth. Our seasons are caused by the axial tilt of the Earth:
You can see from this diagram that each hemisphere has summer when the sun's rays are closer to being overhead, and winter when they're furthest from it. You can also see why the seasons are swapped between the northern and southern hemispheres - the north has summer when the south has winter, and visa versa.
The tilt is measured from the plane of the Earth's orbit around the sun. You can see that the Earth has a pretty decent tilt, enough to produce a pretty significant difference between summer and winter. If the tilt was greater, you'd see greater differences between the seasons.
Now in Eorzea, on the other hand, we don't see any real distinctions between summer and winter. There's a light snow around Starlight, but *every* place gets that. Other than that, every season seems to be basically the same. Corthas is always cold, Thanalan is always hot, the Shroud is always temperate, and these don't really vary with the seasons. You can assume, then, that Hydaelyn's axial tilt is basically straight up and down, making the angle of Hydaelyn's sun's rays the same for any given spot on the surface all throughout the year.
Now, you can imagine you're sitting on the planet, looking up at the sky. You're able to see a circular portion of the sky that's based on the longitude and latitude of the spot you're sitting at, and what time it is. As the planet spins, your visible circle spins with it, which is what lets you see different stars as the night progresses. Now, there are a couple of things that limit what you can and can't see. One of them is the hours of night. You simply can't see stars (except in extreme circumstances) while the sun is shining. The other is your latitude (which is why the night sky is different in the southern hemisphere). You're seeing, on any day, a strip of sky.
As the year progresses, you can see different constellations, though. This is mainly a phase thing: As the Earth goes around the sun, you're seeing a different portion of the sky during the hours of darkness. The axial tilt of the Earth plays into this, too, because the days are shorter for winter and longer for summer. Longer night means more stars you can see.
Since Hydaelyn's axial tilt is basically nil, the only thing that affects what stars you can see is the phase progression from the planet going around the sun: You can still see a different part of the sky during the night different times of the year. Now, I haven't really studied the sky in depth in Eorzea, but I haven't noticed a seasonal difference in the stars. The only thing we can deduce from this is that there's a strangely coincidental correlation between the length of the day and the year, which means that we're always seeing the same section of sky during the night. That's pretty long odds, but as they say, when you eliminate the impossible, what you have left, however improbable, must be the truth.
But what explains this improbable coincidence? Clearly, the answer is magic.
