from the inside at ground level? Andy Probert's sketch in the thread in Trek Art got me thinking what it would actually look like . . . I would think that in the daytime (assuming the central star had a ring of shields to create a day/night cycle) the view would be similar to daytime here on earth, but would the diameter of the sphere be so great that there would be no noticeable curvature? or would the distant mountains seem to fade into the sky? at night one would assume that you'd be able to faintly see the parts of the sphere that are in the daytime area on the other side . . . what would that look like? I know in 'Relics' we saw the land surrounding the opening the Enterprise was pulled in through, and we saw the star at the center . . . I'm just curious how it would look from a scientifically accurate interpretation . . .
I've thought about this a lot because the idea of a sphere fascinates me so. The dyson sphere would be so big (the size of earth's orbit around the sun - 1 AU in diameter) that if you were in a city or on a field within the sphere, you wouldn't be able to tell that the ground is convex, not concave. There would however always be a slight haze over the horizon.
Where? Where?? WHERE?!? Anyway, that's an interesting question. If you've ever seen one of our neighbouring planets brightly lit in the nightsky - one has to wonder how bright the sky would generally be, if there was an Earth-like surface with an Albedo (=amount of light that is diffusely reflected) of about 35% in every direction... very bright, I'd assume. The only way for such a structure (which, by the way, is not exactly what was originally postulated by Dyson) to really work would probably be by covering a large percentage of the inner surface, and possible some solar orbits, with high-efficiency solar collectors that "move" excess energy out of the system, and at the same time bring the average albedo down to a more manageable level.
Yes, Dyson's original idea involved, IIRC, a series of habitable platforms surrounding the central star, not a solid sphere.
in the book "Dyson Sphere" Picard and crew return to the sphere, and discover several sentient races inside the sphere can you imagine how many civilizations could evolve without ever knowing there are others within the same structure? what would their cosmologies be like? to them the world really would be flat, not to mention endless if I remember the surface area would be equivalent to 250,000,000 earths . . . there could be trillions or even quadrillions (is that even a word? ) of people living there very comfortably . . .
I'm thinking that's gonna make a hell of a sonic-boom/shockwave. Need to have some bewildered natives standing in the foreground.
When would it be night-time? If constructed as a solid shell... You'd never be able to experience 'night'. Cheers, -CM-
I would think that the atmospheric haze would obliterate any detail beyond a few hundred miles looking flatly horizontal. But as you tilted your gaze UP you'd see hints of the sphere interior as you'd be looking through less and less atmosphere. But since the interior of the sphere would seem very flat to you, the nearest visible details visible above the atmopshere would be literally hundreds of thousands or millions of miles away, and seen NEARLY edge on, so I don't think you'd be able to see much of anything. I mean, look at the moon, 240,000 miles away and seen flat on and there's nothing to see but light and dark.
Why? The sun would be a limitless supply of energy. Crops growing non-stop, energy flowing through photovoltaic cells powering homes and industry. Just have really, REALLY good blinds in your home or maybe their people got used to sleeping in the light of perpetual noon. That's the whole principle of the sphere; to harness ALL the power of the sun. Who thick do you suppose the shell would have to be? Suppose there would be layers of the shell like a neutronium outer layer and a few dozen miles of silt, dirt and clay? What about oceans and lakes? How deep would they be? How long until the water recycles from the other side of the sphere? Something like 1,000 years or so? Imagine the inside surface of one of them things - the amount of land area 7 billion people would inhabit would be a TINY speck on the inside surface and would take us many thousands of years to travel (by foot) to the other side.
That wouldn't work for the vast majority of lifeforms we know about. Most plants and animals have evolved over millions of years to require both light and dark to survive. As for "getting used to it" -- I suppose it's possible, but it isn't healthy.
the sun wouldn't move across the sky . . . imagine continuous noon! how would the natives measure the passage of time?
Why is everyone so transfixed on the idea of "night" in a Dyson's sphere? As someone pointed out, an ever-present sun would provide limitless supplies of energy. Then someone argued that system "wouldn't work for the vast majority of lifeforms we know about." Well, the big problem with that counter argument is the Dyson's sphere, at least in TNG, is something entirely unique in the history of known space exploration. By definition, the sphere and any life within it are things we don't know about.* If a sphere of that magnitude would take thousands (if not more) of years to construct, it's not inconceivable then that lifeforms would be able to get used to (evolve/adapt) to always present light. Another poster asked how natives would measure time. Why would you even need day or night to measure time? People living near the poles still use the 24 hour clock despite having long days and short nights in the summer, or short days and long nights in the winter. Crews on starships still measure time even when they're on no planet rotating around a sun. I'm sure people intelligent enough to design and build a Dyson's sphere would be more than capable of coming up with a way of measuring time in it. (* This is the big flaw that I find with Star Trek. Alien world and cultures are sometimes all too "human" and we come to think of a lot of things in the Trek universe with human assumptions.) On a related thought, Isaac Asimov's story Nightfall imagined a world that revolved in a solar system of several suns, so that there was always sunlight from some star anywhere on the planet at any given time. But then, when night did fall once every few thousand years all hell broke loose and their concept of an orderly universe went with it. This mind you, was only after a thousand years or so of always having sunlight. So for life living on a planet that rotates, the concept of night and day may seem natural. But then again, wouldn't endless daylight seem natural to the inhabitants of the interior of a Dyson's sphere -- especially after having lived there for millions of years?
I'd go with the arrangement familiar from Niven's Ringworld: have two concentric spheres. The outer one would be this Trek construct which provides habitable area at about 1 AU radius. The inner one would be a more accurate Dysonian construct where giant solar energy collectors orbit the central star, eclipsing it at regular intervals to create swaths of night on the surface of the outer shell. Suitable arrangement of the solar collectors would also result in seasons if needed. Since the bulk of the effort seems to go to supporting an Earth-like environment, one would assume that the imitation would be as perfect as possible. If that weren't the goal, why are the builders bothering at all with the Earthly interior? The far more logical construct for generic life support purposes would be to have the habitats on the outside, where they experience natural gravitic pull without needing constant artificial gravity, and where they don't consume valuable solar collection acreage. But the builders of this thing obviously didn't aim at generic life support... Timo Saloniemi
I don't think a Ringworld-type solution would work in this case. For one, you're dealing with a spherical object, and anything near the axis of the collectors' rotation would be difficult to eclipse (if they're all connected). If they're not connected, you'd need probably millions of these things all with different orbit axes in order to eclipse all portions of the sphere at some point. That would probably be extremely difficult to do without causing anything to crash. Also, I think that the eclipsed areas of the sphere would still be bathed in quite a bit of light, reflected from other portions of the sphere.
I'm gonna take a guess that in these cultures some sort of clock of time-keeping device gets invented earlier than one in a place with more normal day-night cycles.
You would need a much smaller star than a SOL type star because at 1 AU of perpetual light would cause the surface to heat way up without some sorta heat sink, without a heat sink where the F___ am I supposed to sink my heat? I would say make a Dyson Sphere around a small red dwarf, on inner sphere being a dyson cluster that can soak up solar energy and buffer massive solar flares from the red dwarf. It would be smaller and easier (relatively) to build, it would still be immense though. Another benefit would be that you spent a few million years building the damned thing you don't want to have to evacuate it in 4 Billion years when the star goes Kaput in a Spectacular explosion? A Red Dwarf has been estimated to last somewhere around several TRILLION years, making all the time and resources spent building it worthwhile. Plus it would easier to harvest matter from a red dwarf as it's flares could be harvested for raw material ie. Hydrogen that could be used to combine with O2 to make water or fused to make other elements. Your inner dyson swarm satelites could handle this task. A smaller sphere could be rotated quicker leading to gravity along it's inner walls, the poles could be used for manufacturing and energy production. If the red dwarf light wouldn't be good enough for plants you could use the innser satelites to either focus it or create complete artificial lighting for plats etc. I would say a Dyson Sphere the size of 1 AU is rather nice, but with the abundance of red dwarf stars you would be a fool not to make one around a red dwarf, lasts longer, easier to build and easier to hide from enemies as they make less of a gravity dent, heh. No use building something that won't last.
To get an idea of that, would any of the resident 3D artists be able to render a quick&dirty image showing the following? Or would that be too much to ask? * A spherical object with a diameter of about 2AU, with the camera placed inside and at "ground level". * Views might be: looking straight up, straight up with the sun completely shielded by an object, looking towards the horizon * One light source in the center of the sphere, light quality and quantity equaling that of our sun. * Texture of the sphere: some random earth surface imagery, with diffuse reflection set to about 35%.
This is something I have often thought about... If a Dyson Sphere was really so gargantuan, what you see, from the ground level, during the day, would be akin to what you would see in those concept paintings of orbital space colony interiors, except everything would appear flat along the horizon, and after a point, would vanish into the horizon, due to haze, atmospheric effects, and just plain distance. There WOULD be a point, just like on Earth, where if you look up at the sky, it would go from sky blue, to space black, just because of the distances. The way they depicted the Sphere's interior always bothered me, because they made it seem no bigger than a large Spacedock, and it appeared evenly lit from all angles. If a true Dyson Sphere were that large, and the 1701-D had flown that close to the star inside, then the star's light would blot out all visible surface detail, making everything behind and around the ship a dark void.