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  1. - Top - End - #1
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    Default Seeing a Dyson Sphere

    Hello Playground!

    I'm beginning to design my own fantasy world and am slowly trying to fill in holes in my understanding to increase verisimilitude. It is called the Infinite World, and it is a Dyson Sphere encapsulating a yellow dwarf star at a distance of 1 AU.

    Right now I'm wondering if you could see the interior rising up in all directions, or if the human eye would be incapable of seeing that distance. Assuming an atmosphere as thick and moisture-rich as earth's, and no night.

    For those that are interested, and to collect my own thoughts:
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    • There is no day-night cycle, the sun is always shining.
    • Powerful electromagnetic fields generated at the poles filter out much of the harmful radiation, venting it into space.
    • Time is judged based around the moons' moons. Gigantic geostationary space stations are visible over every major continent - appearing as moons of various shapes in the sky. Smaller satellites orbit these stations, taking roughly 24 hours to complete one rotation.
    • Seasons are based on weather patterns. There is the season of drowning - during which immense storms roll in off the oceans unleashing torrential downpours. The season of Growing - during which the skies are cloudy and people can go out to plant and grow crops. The season of Burning, during which the clouds depart and the sun beats down upon the land. The length of the seasons vary from year to year, depending on how long the weather patterns last - some years three crop rotations can be had, in others the rains don't stop until a few weeks before the Burning begins.
    • Massive solar collectors circle the sphere inside the moons, when they cast a shadow upon the land it becomes winter. Winters come once every five years on average, and depending on which collector is casting the shadow upon you - the winter could last anywhere from one month to a year or more. There are two 100-year cycles of winters. in the first, winters are quick, but in the second they can drag on for a LONG time.


    More may come if there is any interest.

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    Default Re: Seeing a Dyson Sphere

    Could you see the Dyson Sphere itself? (I think that's what you're asking.)

    Right, imagine if the sun was the size of your satellites. I'm going to assume each one is the size of Asia, just for overestimation. Now imagine it barely gives off light-maybe equivalent to, hey, Asia. Bright from an orbital perspective, but from an AU? Not so much.

    Basically, one AU is mind-bogglingly far. Unless your satellites are comparable to planets, they won't be seen, and even then it won't be a constant thing. Just an occassional shadow across the sun (if between the sun and planet).

    Also? Setting sounds cool.
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    Default Re: Seeing a Dyson Sphere

    Unless the interior that is rising is the width of the Earth... no. At least not on the other side of the dyson sphere. You'd probably be more likely to see the atmospheric reflection. Consider that Venus is occasionally 1AU from us and is visible as a slightly bigger star.

    I think something like this might be more appropriate. But rather than a glowing dot being a city, it's an moon-sized (or more) construct, or group of constructs.

    I know it's not what you asked about, but if winters last for 100 years then people would move away from winter areas. 100 years is more than most people live.
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    Default Re: Seeing a Dyson Sphere

    Thanks JNA,

    That was my initial thought, that the curvature of the sphere over the vast distance would be so shallow that atmospheric vapor would make it impossible to see the continents immediately surrounding your own; and I knew you wouldn't be able to see all the way across the sphere. My only concern was the ability to see the nearest parts of the curve. But I think you're right - the distances involved would make that an impossibility - especially with an always illuminated atmosphere.

    @Mastikator
    Thanks,
    The cycle of winters are trends, not actual winters. In the first of the 100 year cycles, winters are short - maybe 1-3 months long. In the second cycle they are long - from 3-12 months. They still occur at a frequency of once about every 5 years though. Its only each winter's duration that varies.
    Last edited by Sidmen; 2015-01-27 at 01:55 AM.

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    Default Re: Seeing a Dyson Sphere

    That being said...

    What if you can see it? No one questions it. It's part of the sky, day and night, just a normal, everyday thing. What's that say about where they live, if anyone thinks hard enough about it?

    I don't know if this setting is at all right for this kind of intrigue, but hey. Use it or not, the idea has been presented.

    Edit: *facepalm* I totally whiffed. I thought it was a rock in orbit with they Dyson sphere seperate. Either way, you've got a valid answer, so all's well.

    As a side note, this place has a positively ridiculous surface area. 2.812×10^17 square kilometers. Compare that to Earth-5.1×10^8 square kilometers. This place is about 50,00,00,000 times bigger than Earth.

    How many people live here?
    Last edited by JNAProductions; 2015-01-27 at 02:02 AM.
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    Default Re: Seeing a Dyson Sphere

    Have you read Larry Niven's Ringworld series? Not a full Dyson sphere but a 'small' ring around a sun. It might give you some ideas. I don't think the Ring was as much as 1 AU in radius but the inhabitants could see the Arch - the rest of the Ring arching above their heads.

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    Default Re: Seeing a Dyson Sphere

    My thinking in regards to hollow world type settings in general is that unless the diameter is relatively short or there is no atmosphere (in a fantasy world, maybe instead of air and stuff there is invisible aether?) there would be a limit to visibility that would prevent you from seeing the earth wrap up around the sky. At 1 AU from the center of the sphere, that is definitely the case.

    By that same toke, however, I always like to picture how to the inhabitants of a hollow planet, the horizon would always curve upwards, like they were in a shallow bowl - if an inhabitant were to stand at the top of a mountain, or in the center of a vary large field, it would look strange to us (as people who, you know, live on the surface of an oblate sphereoid and not in a concave basin). Although with a diameter of 2 AU, for the curvature would be so shallow as to be virtually imperceptible.
    Last edited by gom jabbarwocky; 2015-01-27 at 02:04 AM.

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    Default Re: Seeing a Dyson Sphere

    Quote Originally Posted by BWR View Post
    Have you read Larry Niven's Ringworld series? Not a full Dyson sphere but a 'small' ring around a sun. It might give you some ideas. I don't think the Ring was as much as 1 AU in radius but the inhabitants could see the Arch - the rest of the Ring arching above their heads.
    The radius of the Ringworld is 1.02 AU.
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    Default Re: Seeing a Dyson Sphere

    Quote Originally Posted by JNAProductions View Post
    As a side note, this place has a positively ridiculous surface area. 2.812×10^17 square kilometers. Compare that to Earth-5.1×10^8 square kilometers. This place is about 50,00,00,000 times bigger than Earth.

    How many people live here?
    Hehe, no worries.

    But yes, a Dyson sphere is utterly massive - that's why I named it the Infinite world, because it is from the perspective of the people living there. My question was directed mostly because I'm filling a new sketchbook with this world's information, and am currently writing a preamble from the perspective from the Master of Maps at the archives of the Tower that Isn't. If you could see the curve, then he would point this out as proof of his claim that the world isn't actually infinite, just utterly huge.

    Some trillions of people live on this world, but the vast majority aren't in contact with the others. It is a medieval fantasy setting that includes magic (since it's intended for use with D&D 5e, and everyone in that system has magic). So some of the answers can be "it's magic", but I want as few as possible of them to be.

    Quote Originally Posted by gom jabbarwocky View Post
    My thinking in regards to hollow world type settings in general is that unless the diameter is relatively short or there is no atmosphere (in a fantasy world, maybe instead of air and stuff there is invisible aether?) there would be a limit to visibility that would prevent you from seeing the earth wrap up around the sky. At 1 AU from the center of the sphere, that is definitely the case.
    Thanks, that's further reinforcement of my initial suspicion. There is air in my world, and it does have water vapor in it. I know the atmospheric interference on earth limits our sight to about a dozen or so miles, but I wanted to add some more brain power, or those with more knowledge to my thoughts.


    EDIT: Oh, and I have unfortunately not read Ringworld.
    Last edited by Sidmen; 2015-01-27 at 02:13 AM.

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    Default Re: Seeing a Dyson Sphere

    What's Outside the Dyson Sphere? Speaking as a player who likes to push things, that's something you might want to give thought to.

    In addition, just as a minor fluff detail, Star-Forged weapons, made from chunks of White Dwarf. No idea on the crunch, but could make a cool artifact.
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    Default Re: Seeing a Dyson Sphere

    Read it. The first few chapters on the ringworld will give you some truly mavelous ideas.
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    Default Re: Seeing a Dyson Sphere

    Another fantasy setting with a Dyson sphere is the Demon City in Exalted.

    More specifically, the Demon City is a giant living structure of tarnished brass and black basalt bones centered around a hateful emerald star that casts no shadows. Due to the twisted nature of Malfeas, the green sun appears directly overhead from the viewpoint of any and every layer of the city simultaneously. Malfeas is insanely massive, yet still absolutely crowded with manic, braying demons, and his spiteful plate tectonics will grind two layers together at a time, killing untold thousands.

    It's surrounded on all sides by an endless desert, which seals it away from the world it once ruled over; a wind runs through the Demon City whenever and wherever silence falls, killing everyone present; "lower" levels of the Demon City are flooded by a caustic sea filled with even more terrible monsters; buildings shatter in the wake of the Black Boar That Twists the Skies.

    Also it's hella fun to play in.
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    Default Re: Seeing a Dyson Sphere

    Not to spit into other peoples soup: But why?

    So far, it seems like for people in this world everything is exactly the same as on a planet, except that the sun never sets. A few scientists might figure out that the infinite flat surface is actually not infinite but very slightly curved, but what effect does that have on anyone else?
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    Default Re: Seeing a Dyson Sphere

    Ages of ages ago I'd read a story, part of which was set on a Jupiter-sized rocky planet with a breathable atmosphere. The author had suggested that so much air would refract the horizon upwards, giving you a concave horizon on a convex world. If that holds water (or rather, bends light), then you would definitely have a bowl horizon. If not... you still might get a bowl horizon. But consider that you are not looking at the outer surface of a 3900 mile radius spheroid. You are looking at the inner surface of a 93 million mile radius sphere. With a curvature roughly 25,000 times shallower, it may look pretty flat.

    What is going to limit your horizon is distance and scatter. At some point, you will not be able to make out detail save at the largest scales, or with super-to-supernatural acuity. But at some point you will run into scatter from the atmosphere. Light bouncing off the air molecules and water vapor, shifting and fading color, washing out detail, and distortion from temperature variants will make everything disappear into a haze of distance. The horizon doesn't fall off so much as disappear into the ether. At first blush, this sounds like "fading into infinity" to me.

    But let's play a game. set a tangent line ABC to a sphere, intersecting at B. Set another line (BD) at, oh say a 10 degree angle with the tangent line from B to where it intersects the sphere again at D. What's the distance between B and D? If I'm doing my math right, that's 16.14 million miles. 10 degrees up from a "flat" is looking at something 1.4 light minutes away, with light bouncing through two layers of atmosphere on one hell of an oblique. Best guess, you aren't seeing crap for detail. A moon-sized object at that distance will appear about 1/6 the size of our moon.

    To the characters in the setting (assuming they're local), this is normal. What you do is set up the understanding of the world, and change one detail: Things don't disappear over the horizon, they disappear *into* the horizon.

    Quote Originally Posted by JNAProductions View Post
    What's Outside the Dyson Sphere? Speaking as a player who likes to push things, that's something you might want to give thought to.

    In addition, just as a minor fluff detail, Star-Forged weapons, made from chunks of White Dwarf. No idea on the crunch, but could make a cool artifact.
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    Default Re: Seeing a Dyson Sphere

    Quote Originally Posted by JNAProductions View Post
    What's Outside the Dyson Sphere? Speaking as a player who likes to push things, that's something you might want to give thought to.

    In addition, just as a minor fluff detail, Star-Forged weapons, made from chunks of White Dwarf. No idea on the crunch, but could make a cool artifact.
    "Chunks" of White Dwarf? The crunch is that there is no crunch. White dwarfs are stars, and as such, are made up of hydrogen and helium gas. Have to come up with another source of "star metal".
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    Default Re: Seeing a Dyson Sphere

    Notably, the moons orbiting will be visible only to bands of the world that coincide in some way with their orbit. The orbit of the moons, if they are coplanar, will also define directions, but only for those regions which can see them.

    Further away from the band in which the moons orbit, there will be no signs of such things.

    Alternatively, there could be moons orbiting in many different planes, which would require them to also orbit at massively different distances. The ones closer to the sun would have to be bigger to remain visible on the surface of the sphere. Also, where moon paths cross, people would have different perspectives on their paths than where there is only one moon that passes into view, or where moons apparently travel similar paths.

    Finally, moons would not "rise" and "set," but would instead approach and recede. They fly overhead more like an airplane seems to, appearing in year-long cycles as small specks in the horizon, growing and separating out to be overhead, then shrinking and receding into the opposite horizon.

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    Default Re: Seeing a Dyson Sphere

    The oceans on the planet would be unstable. Rendezvous with Rama by Arthur c Clark discussed this a bit. Because the surface of the ocean is heated and the outside of the Dyson sphere is not, it would cause ice to freeze at the bottom of it and rise to the surface. The massive quantities of ice fracturing and moving could cause massive waves and storms as well as massive fluctuations in water temperature. In ramas case, he crafts temperature rising as a whole caused a superstorm resembling a hurricane which threatened the safety if the exploration crew. I know Arthur c Clarke actually spoke with climatologists to come to this conclusion, and not being one I can't do it justice. Just keep in mind in this sort of environment, any storm has a harder time dissipating, and the fact that the ground is not heated from a central core as our planet is will cause problems.

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    Default Re: Seeing a Dyson Sphere

    Keep in mind, if the Dyson sphere is not rotating, there will be no Coriolis effect to cause storms to swirl. And even if it is rotating, the rotational speed will be so slow that most storms will be unaffected by it. So you'll be unlikely to get huge hurricane superstorms. You'll still get tornadoes and probably mesocyclones, but there will be no jet streams or polar vortices.

    How thick is your atmosphere? I think ours "ends" at about 100 km.
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    Default Re: Seeing a Dyson Sphere

    Actually, that brings up another point: due to how fields work (in this case, gravitational fields), there is no gravity on the inner surface of the sphere. All the gravity pulls towards the star and other bodies orbiting within the sphere. (You would see a similar effect if you could sit at the center of the Earth.)

    To get gravity, you'd need to rotate the sphere. This would, in effect, cause there to be a gentle-but-increasing slope as you moved away from the equator, with the equator being the "bottom" of the world, gravitationally-speaking. There would be some point where the gravitational pull towards the equator would balance its "out" force with the "in" force of the central star, which would cause the inner surface of the sphere to be sheer walls there. Go higher still, and the gravitational force felt would be strictly towards the sun, causing the inner surface here to feel like a ceiling as you get to the poles. A ceiling over an AU drop to a burning hot star.

    You'd also have thinning atmosphere out that far, as, like any fluid, it would be pulled "down" towards the equator.

    Also, go fast enough against the rotation of the sphere, even at the equator, and you will start to feel an upward force as you negate your centrifugal force.

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    Default Re: Seeing a Dyson Sphere

    Well, as far as the gravity goes:

    Where did the sphere originate? A species evolved enough to have created the sphere, to be able to completely encapsulate their own star, probably had sufficiently advanced gravity technology. Advanced enough to at least create a facsimile of Earth-norm gravity.

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    Default Re: Seeing a Dyson Sphere

    There does need to be a certain amount of "magic handwaving" for the concept of the dyson sphere to exist, as they are inherently unstable. A slight shift away from being perfectly centered on the star will quickly bring the whole thing to ruin, as the central star is pulled to the closer side of the sphere until it hits. Decide what you want to have "magically" working, and extrapolate from there.
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    Default Re: Seeing a Dyson Sphere

    Neat idea for a Hard High Science Fantasy setting (that's a term I coined just now. It means a setting that mixes high fantasy and hard science fiction. Like Lord of the Rings meets Interstellar). Let me offer my two cents:

    Quote Originally Posted by Elvenoutrider View Post
    The oceans on the planet would be unstable. Rendezvous with Rama by Arthur c Clark discussed this a bit. Because the surface of the ocean is heated and the outside of the Dyson sphere is not, it would cause ice to freeze at the bottom of it and rise to the surface. The massive quantities of ice fracturing and moving could cause massive waves and storms as well as massive fluctuations in water temperature. In ramas case, he crafts temperature rising as a whole caused a superstorm resembling a hurricane which threatened the safety if the exploration crew. I know Arthur c Clarke actually spoke with climatologists to come to this conclusion, and not being one I can't do it justice. Just keep in mind in this sort of environment, any storm has a harder time dissipating, and the fact that the ground is not heated from a central core as our planet is will cause problems.
    There's a simple solution to this: The aliens who built the Dyson Sphere built heaters that generate upper mantle-like temperatures at the very edge of the sphere (the deepest areas underground to the inhabitants). The heaters would be powered by the immense amount of solar energy that the orbiting satellites and the Sphere itself generates. This solves the freezing ocean and allows for natural magma to form underground, creating natural volcanoes and giving dwarves a way to smelt stuff in an awesome way.

    Quote Originally Posted by Joe the Rat View Post
    Outside? That's the Underdark.
    Actually, the bottom of the world would likely be made of an extremely strong material. Considering the tech-requirements it would be a carbon-nanotube/buckyball alloy at the very least; I'd recommend neutron-degenerate matter. If, somehow, one were to breach the super-durable "skin" of the Sphere, they would be exposed to the vacuum of space. The breach would begin sucking out the atmosphere. However, the civilization that created the Sphere (I'm going to call them the Creators) would probably have foreseen that scenario and stationed repair drones/supplies on the "skin" to seal any holes in the Sphere. The drones would be powered by the incredible amount of energy produced by the Sphere, and with the Creators' super-science could last for billions of years (I think it is proper to use Clarke's Third Law here considering that the Creators had the capability to build a structure the size of a small solar system and planets to inhabit it).

    Acutally, I have an idea. What if the Creators were a highly advanced version of humanity thousands of years in the future? They have started to Dysonize the galaxy (I'm going to assume that they have wormhole technology because without FTL travel and communication such an arduous construction project would be nearly impossible. Another assumption I am making is that future humanity has merged itself with the machines, and now is a seamless fusion of biology and technology. My last assumption is that future humanity does not use magic if magic is actually a supernatural force and not just supertech left behind by the Creators as I will elaborate later), and as an experiment, decided to recreate the fantasy worlds of their past fictional works by seeding one of those Dyson Spheres with life from Earth and leaving AIs to direct the evolution of creatures on the Sphere over billions of years so that a fantasy environment (metahuman subspecies, normal humans, etc.) would be created. If we take this even further, why not make magic just a product of godlike nanotechnology, and deities said AIs? Then this setting would have a good explanation for why magic exists in an otherwise scientifically-hard world. There would be ominous black towers dotted all over the landscape, made of nearly indestructible (to fantasy methods, anyway) materials, channeling "magic" or performing some other task unknown to such primitive inhabitants. The moons the elves worship are actually giant artificial planets harvesting ludicrous amounts of energy to be used by the Creators and the Sphere itself. And some of the God-AIs might have gone rogue over the billions of years that they were operational, and now seek to lead their created races out of the Sphere and into the depths of space.

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    Default Re: Seeing a Dyson Sphere

    Quote Originally Posted by Lord Torath View Post
    There does need to be a certain amount of "magic handwaving" for the concept of the dyson sphere to exist, as they are inherently unstable. A slight shift away from being perfectly centered on the star will quickly bring the whole thing to ruin, as the central star is pulled to the closer side of the sphere until it hits. Decide what you want to have "magically" working, and extrapolate from there.
    Actually, this isn't quite true. Inside the sphere, the gravitational field of the sphere itself is flat. There is equal force in all directions, no matter where you are, due to its gravity.

    All objects inside its center experience gravity as if the sphere were not there. This includes the central sun. So if it drifts, it does so only on its own momentum. No gravitic force will excacerbate the problem. That doesn't mean drifting wouldn't be a hazard; it would, unless corrected, still cause the sphere to impact the sun...eventually. Just due to momentum from whatever started the drifting.

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    Default Re: Seeing a Dyson Sphere

    Does this depend on the relative masses of the two bodies, sphere and star? As the sun "wanders," it will be closer to one side of the sphere, and will pull harder on that side than the other. But at the same time, there is now more mass on the other side of the sun, although it's farther away. So the two forces could continue to be equal and opposite, for no net effect. Hmm...

    I suppose I could just go spend a few hours on Atomic Rockets if I really want to come down Stupidity Hill.
    Last edited by Lord Torath; 2015-01-27 at 03:17 PM.
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    Default Re: Seeing a Dyson Sphere

    Thoughts on what you see when you look up.

    Ok, so the horizon would look REALLY odd to someone used to a round world. The land curves UP, so you could see a LOT further than normal given a flat expanse. You could see ships DAYS before they got to shore. Navigation may be easier because landmasses could be seem weeks from landing. Climb a short mountain and you should be able to see as far as your eyes can make out detail.

    The main constrain would be the size of the object you are looking for and the atmosphere. The air causes light to scatter. Blue light scatters much more than other light due to an odd interaction with air. It's why our sky is blue around the edges and gets whiter as you get closer to looking directly into the sun (the blue light hitting the edges of the atmosphere scatters in your direction. This is also why sunsets are red (blue light scatters elsewhere, leaving the sun reddish).

    It would look like the horizon is cloaked in a fog after a point. You can clearly see the ground from 30,000 feet up, so you are likely looking at 10x that to get enough distance that scattering blocks your view. Even a short tower would be a crushing tactical advantage for a defender. Get up above the tree level and you can see anything not behind something else. moving more than a few men would be impossible to hide.

    After looking up past about 2-5 degrees the sky would turn the expected blue color. The ability to see land would fade into a blue haze as the light scattered from the sun became more powerful than the light reflecting off the land behind it. It would not be a solid line, but a fading effect. Winter would reduce this significantly and allow you to see far further up the edge of the world.

    Then you would look up and see the sun. Objects, like your moons, would have to be very large to be seen. The problem is that light is coming from behind them, this means very little light is coming off the surface pointing towards the land. Unless they eclipsed the sun they would appear as faint outlines in the sky.

    An example using our moon during the day. Note the dark side is almost invisible.


    Measured in AU, the moon is VERY close and VERY small. Something at .5 AU (half way between your sun and land) would have to be HUGE to be seen. Consider making them glow somehow, or very shiny. A large shiny object could be seen from the opposite side of the sun. It would have to be very shiny and very large though. Visible during the day is a large hurdle. (a mirror the size of a planet with perfect albedo of 1 though... maybe. Depends on the planet.). Think less visible object, more glowing star though, and faint as it is in a losing battle with the sun. They would be invisible when on the land side of the sun, only to suddenly appear in the sky when they turn 90 degrees to the sun, but disappear again when they pass too close to the sun and it's light blocks them out. They would reappear on the other side though, and disappear as they turn once more to face away from the land. The moons, well it would take a VERY large object to hold a visible moon.

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    Default Re: Seeing a Dyson Sphere

    Quote Originally Posted by Sidmen View Post
    Thanks, that's further reinforcement of my initial suspicion. There is air in my world, and it does have water vapor in it. I know the atmospheric interference on earth limits our sight to about a dozen or so miles, but I wanted to add some more brain power, or those with more knowledge to my thoughts.
    I am currently looking at a mountain over 200 miles away, it is barely visible, but there. Today it is quite cloudy and a bit foggy; On a clear day, the mountain is easily visible in great detail.

    The planets are easily visible in our night sky. If you know where to look, you can even see many of them in the middle of the day, including Jupiter. The far side of the sphere would be closer than Jupiter ever is to the Earth, and is much larger. With clear skies, it should be easily visible.

    This assumes that the atmosphere is a shell along the inside of the sphere with a depth similar to Earth's. If the entire sphere is filled with atmosphere, it would have enough mass to collapse into a black hole under it's own gravity. This would limit adventure possibilities.
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    Default Re: Seeing a Dyson Sphere

    Quote Originally Posted by Fouredged Sword View Post
    The main constrain would be the size of the object you are looking for and the atmosphere. The air causes light to scatter. Blue light scatters much more than other light due to an odd interaction with air. It's why our sky is blue around the edges and gets whiter as you get closer to looking directly into the sun (the blue light hitting the edges of the atmosphere scatters in your direction. This is also why sunsets are red (blue light scatters elsewhere, leaving the sun reddish).
    Actually the sky looks darker, not lighter, the closer you get to looking straight up. Go outside and give it a look.

    Also, you won't get quite as much advantage from height as you might think. The curve of the sphere is very gentle. If you had a 12" block, you could put a (perfectly straight, perfectly rigid) ruler on it that's 375 miles long before both ends would touch the sphere. You know, assuming there are no hills, buildings, trees, or other obstructions in the way. Yes, towers will help, but not much more than they do here on earth.
    Quote Originally Posted by Akodo Makama View Post
    The planets are easily visible in our night sky. If you know where to look, you can even see many of them in the middle of the day, including Jupiter. The far side of the sphere would be closer than Jupiter ever is to the Earth, and is much larger. With clear skies, it should be easily visible.

    This assumes that the atmosphere is a shell along the inside of the sphere with a depth similar to Earth's. If the entire sphere is filled with atmosphere, it would have enough mass to collapse into a black hole under it's own gravity. This would limit adventure possibilities.
    Keep in mind, there is no night. Venus is visible (barely) during the day at certain points in its orbit, so it's not impossible, but you're not going to be able to see anything within probably 30 degrees of the sun, unless you're having an eclipse from one of the "moons."
    Last edited by Lord Torath; 2015-01-27 at 04:14 PM.
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    Default Re: Seeing a Dyson Sphere

    @ Sidmen
    Are you going for a "Hard High Science Fantasy" setting or just a high fantasy setting?
    In the latter case, the god(s) created the world and ignore RL science. Just remember to apply the same rules every where that shouldn't have a specific exception. Down is towards the ground, up it towards the sun. Winters may or may not be predictable in occurrence or duration. Objects seem to fade off into the horizon, etc. Sometimes worrying to much about the science of a fantasy world keeps you from telling interesting stories within it.

    Pryan, the world of fire in the Death Gate Cycle is effectively a Dyson Sphere with 4 suns in the middle. There is some RL science in the backstory, but the entire universe operates on magical reasoning.
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    Default Re: Seeing a Dyson Sphere

    This is a ringworld:


    Note the inner ring of shadow squares, casting night on the outer ring. This makes the view from the surface look like a heaveenly arch, like this:


    A Culture Orbital (or for videogame fans, the more recent Halo ring) looks like this:

    With day and night being provided by the ring itself- it takes 1 day to make a full rotation, meaning the sun sets behind the ring and rises 12 hours later. From the surface, the ring is much more visible:


    A dyson sphere would be as visibe as that first arch... but covering the whole sky.

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    Default Re: Seeing a Dyson Sphere

    Awesome discussion, guys. Really helps me in my own thoughts/answers questions I hadn't even thought to ask. So many things to reply to, so quotes would make it far too messy. Sorry if I miss anyone.

    What's outside the sphere?
    The sphere resides inside the Ephemeral Chaos, a point of solidity inside a sea of ever-changing reality. If you exit the sphere - somehow - you end up in a place where the laws of reality change based on the whims of the nearest fae creature.

    Malfeas
    I've long since given up on waiting for 3e Exalted to come out, and can't overlook 2e's problems. In a few years, when the Dragon-Blooded book comes out, I'll play in Creation again. So, yeah, that's a setting I'm defiantly using for inspiration.

    But why a Dyson Sphere?
    Simple, my friend. It's an excuse for me to employ my new sketch pad to detail theoretically limitless continents, archipelagos and nations. By setting up several conceits; these can all occupy the same world and be visited by my players.

    Star Metal?
    This does exist in my world, as debris that sometimes falls from the sky. Its essentially my version of Valyrian Steel or Adamantium - an incredibly rare and durable metal made using advanced metallurgy.

    The Moons and their Eccentricities
    The moons aren't actually moons, they orbit the sun at the same pace the sphere rotates, locked in geostationary orbits above each major continent on the sphere. They do glow with their own internal light, and aren't natural bodies - they're constructs.

    Oceans freezing and causing storms
    That's actually really cool and interesting. But I'm expecting the exterior of my sphere to be incredibly hot, not cold. As heat is drawn from the "surface" of the interior and stored in heat sinks between the shell and the land/water before being radiated through vents.

    Gravity and rotation
    I suspect this is one area where I will have to say "because magic". The exterior skin of the sphere is made from stardust (unapologetically stolen from the Star Force series), which is essentially Neutronium, so it does have the mass to generate it's own gravity, and the sphere will be slowly rotating, but those things probably won't cause the effects I want. So, as was suggested, some of the energy gathered by the collectors will be powering artificial gravity wells.

    Where did the Sphere Originate?
    In the most clinical way of telling it: a great power got tired of the ever-changing nature of chaos, so he built a shell around himself to keep them from bugging him. Bored, he started civilizations on the inside of his shell like a human may start up an ant colony. As a creature that likes order, he's built automated systems set in patterns to administer his colonies of living beings.

    The Creators
    A lot of gutza1's post is very similar to what I already had planned for my setting. The creator isn't a hyper-advanced human, but other than that... Magic comes from the various animating intelligences of the satellites and other monitoring spirits set to watch over the creator's pets. I hadn't considered using nanotechnology to be the means of the magics - but other than that: the AIs absolutely are the Deities and spirits that inhabit the lands, they do provide power for the casting of spells, and some of them absolutely have gone rogue to the creator's plan.

    Looking at a mountain
    Yeah, sorry. My 12-mile figure was to make out a human-sized object. Proportionally larger objects (like a mountain) can be seen at increasing distances.

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