Re: The Science of Atys
Posted: Fri Apr 07, 2006 4:40 pm
All true.... but what revolves around what depends on mass and not on size. No matter how large Atys is, if it has comparable gravity to earth, it can't have more mass a star.alurach wrote:Assuming the sun is fusing hydrogen the way our is, it can't be too small, at least the size of Jupiter, and that would mean that Atys is HUGE, and I mean ENORMOUS. However, there is reason to believe that atys isn't very dense, below the Prime Roots is just another layer of caves, and so on it goes down. That way, for earth-resembling gravity it can be and has to be quite large.... or is it the opposite?
I believe a star needs to be at least a few dozen times the mass of Jupiter to initiate hydrogen fusion. Ofcourse, who knows what the Karavan could come up with to trigger hydrogen fusion inside a normal gas giant? It wouldn't be able to burn nearly as long as a star before running out of fuel. But Atys doesn't seem to be very old - a few thousand years maybe, so it wouldn't need it's sun to burn for 5 billions years.
Oh, good one, I hadn't even thought about that. If Atys was the more massive body, the ring would be around Atys instead of around that other planet. So Atys must be the moon. That makes the Atys orbit a lot more complicated though.iwojimmy wrote:As part of my own preconceptions about how the universe works.. if there is something (naked eye) visible in the sky with a ring around it, we are going to be in orbit around that... obviously not in the same plane, but a ring system would not survive on a secondary body.
Yes indeed, the result being that the orbiting body moves slower the further away it is. So if there's an eliptical orbit responsible for the day and night(whether it's Atys around sun or sun around Atys), the night would be longer than the day. A lot longer. The night's actually shorter than the day.kibsword wrote:I think the formula is T^3=R^2 or something simular. A body crosses the same area of its orbit in equal periods, in other words Areal velocity being constant. Think thats Kepler's 2nd law.
And as already noted, an eliptical orbit would make a stationary position of the sun impossible too, since a planet rotates at constant speed.
However, I think this theory could solve that:
Now if Atys moved around the planet in an eliptical orbit turned towards the sun, Atys would move slower when it's closer to the sun, and the days would be longer than the nights. As for the sun always being in the same position, I say that Atys doesn't rotate around it's axis. Rather, the plant of Atys (which obviously can only cover half the planet, the other half is in eternal darkness) always turns to face the sunlight. Since we're on it, we always see the sun in the same position.kibsword wrote:1 - The Sun is a normal sun, Atys rotates around the ringed planet we see in the sky (as does the other moon), but at an angle to the normal planetry plane, and does not spin relative to the sun. As a result we always see it at the same point in the sky, and gets closer and further away due to orbiting the planet. However, the sun changes in visible size so much that this would have to be a very big lunar orbit relativly speaking.
Only problem it leaves is that the ringed planet would have to become smaller as the sun becomes larger... as far as I can tell it doesn't.
Yeah, that works too, though I couldn't imagine where they'd get the energy from to supply an entire planet.kibsword wrote:2 - The Sun is not a sun at all, it is a technological or magical device in the sky that changes size due to the seasons, it is in a geostationary orbit around Atys, which rotates around the ringed planet as normal.
How about my earlier theory that the sun IS a real sun, but not a 'natural' sun? It's a gas giant or a brown dwarf that's artifically being stimulated to maintain hydrogen fusion. Probably by the same beings that tried to teraform Atys. Perhaps whoever made it didn't fully control the process and accidently turned it into a variable star that brighten and dims periodically within one Atysian day. (Variable stars with a period of one Earth day exist, though none with such a huge variation as the Atys sun.)
Or perhaps they do control it and simple choose to 'turn down the light' a few hours every day, to simulate a day/night pattern.
OR, perhaps the process simply isn't stable. Perhaps once they ignite the 'sun', it steadily fuses hydrogen and shines brightly for a number of hours. But the fusion process can't maintain itself like in a real star, and the sun slowly dims down again. So every 24 Atysian hours, they shoot another laserbeam or whatever into the sun's core to fire up the fusion again.
Hmm, I like this theory. Artificially igniting a gas giant to provide the energy for a teraforming planet. Science fiction at it's best
.. iv had more fun reading it thne playing the game for the past week or so o.o ..ill be keeping an eye on this hope it keeps going for awile...atleast till i can start enjoying the game again