Placio
Because we obviously have an artificial light instead of a sun I would propose a couple ideas:
1. Atys does not orbit a star, the star does not emit sufficient usable light, or the orbit of Atys is very far from the star of this system.
Third possibility, Atys orbits a star but is tidally locked and we are not on the side facing the star. (This would mean that any "realistic" Stars would have a motion that was linked to the year, not to a day.
We might even be in a Trojan position defined by the ringed object and the star.
Placio
2. Assuming that the artificial light is a technological structure (most likely in this case) it suggests the Karavan/MegaCorp have access to fusion. Its the only energy source in our current understanding of physics that would be able to produce energy comparable to a stars' power- because it is actually where star get their power from. But if they have fusion, why the heck did they bother with Atys? They could just take materials from Atys or the ringed planet or the orange moon and create a giant rotating habitat or floating city on the ringed world.
You are *assuming* that the sun is technological. It might also be magical. Even if it is technological, placed there by the Karavan, and based on fusion, that does not imply easy transmutation of the elements. Remember, we don't really know the Karavan's agenda, and we only have the word of the Kami that the Karavan are here to strip-mine Atys.
By the way, we know that when we look at what is apparently a solid object in the sky (at night after the flares die down) we see something that looks about like the Moon does in the skies of Earth. If we assume an angular diameter of 0.5 degrees (Moon from Earth), and a distance of 250km (midway in my estimates), the diameter of the physical object is only 2 kilometers! That's not nearly big enough to support fusion, though it might be big enough to be a radiator for a fusion reactor. Note that it is also *much* smaller than Atys, which extends at least 35 km without significant deviation from planarity in the New Lands. ((There is not enough information to say from ingame measurements whether or not the New Lands are on a large sphere or on a large plane. -- in computer game space, of course, they are on a plane.))
In-game, given the information on which I based my True Map, and assuming that there is a possibility of 5% error (assumption for the purposes of demonstration -- my actual error in lining things up is less than 1%) that might show curvature of the surface, the *minimum* diameter of Atys is 220 km. Much more likely, given that it has an atmosphere, is > 8,000 km. ((Of course the atmosphere could be held in by technological or magical means, but unless we have a substantial diameter the gravitational constant would be very low. I think we can discount artificial gravity applied on a planetary scale.))
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Remembering Tyneetryk
Phaedreas Tears - 15 years old and first(*) of true neutral guilds in Atys.
(*) This statement is contested, but we are certainly the longest lasting.
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