Interesting Megastructures

[Metaphysician]

Has anybody here used in a game some form of megastructure outside of the usual Dyson spheres and ringworlds??

[Outsider]

Re: Interesting Megastructures

 

How mega is mega?

 

An arcology can be pretty big, but (of course) its nowhere near a dyson sphere. Still, one that was 10 km on a side and 3 km in height (1 km underground, 2 km above) with a floor every 4 meters would have 75,000 square km of total horizontal area. Making it about the size of Austria or South Carolina (discounting multifloor buildings in those two entities) after a fashion.

 

For game play reasons it would probably be best to make it largely fireproof, and structurally (nigh) invulnerable.

[Agemegos]

Re: Interesting Megastructures

 

Has anybody here used in a game some form of megastructure outside of the usual Dyson spheres and ringworlds??

 

Do you count beanstalks and rotorvators?

 

I suggest you examine this site: http://www.aleph.se/Trans/Tech/Megascale/index.html.

 

And perhaps read Indistinguishable from Magic by Robert L Forward.

[Agemegos]

Re: Interesting Megastructures

 

How mega is mega?

 

By convention, the cutoff for megastructures is that they have structural (ie. load-bearing) components at least one megametre (one thousand kilometres) long.

 

No, the Great Wall of China doesn't count, because it doesn't carry any loads along its length: it is only structural in the vertical.

[Sociotard]

Re: Interesting Megastructures

 

Shoot, I'm trying to remember what David Brin called them in his uplift novels, but he mentioned a varient of a dyson sphere that covered its interior surface with fractals. it was interesting.

[Nyrath]

Re: Interesting Megastructures

 

You can find plenty of interesting ideas here

[Bill_CCHKK]

Re: Interesting Megastructures

 

And perhaps read Indistinguishable from Magic by Robert L Forward.

Another good read is "Bigger Than Worlds" by Larry Niven, in one of his short story collections (A Hole in Space, maybe?) It covers large, world replacing structures from asteroid bubble worlds to galaxy-sized Dyson spheres with the living area on the *outside*. I'm especially fond of the cosmic macaroni.

 

Also, this is an interesting article on his web page that compiles books using world-size structures. (EDIT: Oops, it's also just a link to a copy of the article Nyrath referenced above).

[Pfathai]

Re: Interesting Megastructures

 

In Iain M. Banks's novel Look to Windward, an interesting megastructure is featured, but only vaguely described: the airsphere.

 

Basically, it is two HUGE (on the order of a brown dwarf) spheres stuck together, filled with breathable atmosphere, spinning for gravity. It is surrounded by several "sun-moons," moons with huge spotlights on them to provide light, moving around the airsphere and shining at different intensities, in a chaotic pattern. It moves around the core once every galactic year (forgot how long that is, but its hundreds of millions of years)

 

Inside, the most important creatures are the Megalithic entities: huge (kilometers long) gasbag creatures that are the equivlant of solid land, great living, moving islands in a sea of air. On their surfaces and inside, they support ecosystems, of symbiotes, parasites, residents, and several races of sapients, sometimes guests from the outside. They are hundreds of millions of years old (the airspheres were built by an Elder Race billions of years ago), and are very open- but inscrutable. Very friendly, but kill one and you'll be hated till the end of time.

 

The spheres contain other creatures, too, winged and gasbag. They have, at the bottom, a detrius neck, to which falls waste, which is ejected every few millenia, leaving moon-sized droppings, in a ring through the galaxy.

 

An airsphere can be a fascinating, very alien vista for players to visit, even the setting of a campaign, possibly one involving an empire trying to take over the sphere, versus its biotech-using inhabitants.

[JSenecal]

Re: Interesting Megastructures

 

Has anybody here used in a game some form of megastructure outside of the usual Dyson spheres and ringworlds??

 

Before ringworld was published I had a campaign set on a donut shaped world, Tor. Tor was much smaller than a ringworld, but bigger than a normal world.

 

Tor was hollow, with a cosmic string (effectively a loop of black hole) at it's core. Tor had a rapid spin which provided gravity on the inside, and reduced the gravity on the outside, but it still had various gravity going from 1.5G on the mountainous outside to only .5G on the lowland sea. Storms on Tor would last for days, sometimes as long as an hour. Different peoples lived in the different areas, I used fantasy names for them, but this was a technological game.

 

Tor was VERY old, billions of years, maintained by a computer that had been instructed to maintain to do so indefinitely. It realized this wasn't possible with an industrial civilization, so it reduced the population to a pre-industrial civilization and kept it there. Some technologies were never allowed to develop, others had been perfected by billions of years. Each race had it's own specialty, bred into it's genes (idea stolen from Mote in God's eye).

 

Eventually the sun Tor orbited was getting old, and the master computer moved Tor back in time to a fresh sun (it had plenty of time to plan this). The sudden appearance of a massive planet was detected on Earth, and hundreds of years latter a ship was sent to investigate. They attempted to land, but the strange and unexpected gravity gradients around Tor led the ship to crash with the scientists scattered around the planet in life pods.

 

The computer was considered a god, but wasn't worshiped. The various maintenance and surveillance robots were known as godlings. People could tell requests or wishes to the godlings, and sometimes these would be granted. The computer was supposed to serve the people after all, and it continued to do so where such service wouldn't cause problems. Not that it was a kind god, when populations grew too high in an area, it would transport in savage races to reduce them again.

 

These newcomers were a disruptive influence so the world computer summoned exceptional individuals from around the world to form a team (the PCs) and sent them to retrieve the scientists. It couldn't act directly because it was limited what it could do to individuals. Also they knew at least something of banned technologies (electronics primarily), and recognized godlings as the robots they were.

 

Meanwhile the scientists found themselves in a strange land indeed. These "primitive" people had allows that their own metallurgist could only dream of, mechanical devices of unbelievable tolerances and complexity, and advanced bioengineering.

 

The resulting game was like Pern in that is was a fantasy appearing setting with a SF background.

[Curufea]

Re: Interesting Megastructures

 

I've contemplated using Orbitals from Iain M. Bank's Culture series. "Small" ringworlds that orbit a sun, rather than encircle it, about 3k km in diameter.

See-

http://www.cs.bris.ac.uk/~stefan/culture.html

 

I wonder if their ships (especially the General Systems classes) would be classed as megastructures?

 

Technically, everyone uses at least one megastructure - the universe

[Xavier Onassiss]

Re: Interesting Megastructures

 

Apologies posting something from a non-Hero campaign.

 

Last time I ran Traveller, I used a ring around a planet in synchronous orbit, with several towers connecting it to the surface. I don't have the exact figures with me, but it was "relatively" small, due to the planet's small size and rapid rotation. The ring averaged about 1km in diameter, and was somewhat underpopulated with about 90 billion people. The PC's never got around to exploring most of it, for the usual reasons....

 

Fortunately, the PC's were on vacation there, so the adventure didn't conclude with the destruction of the entire orbital construct. (For once. )

 

The real mega-structure was inside an Ancient's portal; a pocket universe containing a dyson sphere constructed around a black hole. Which of course, they destroyed. Accidentally. No, really....

 

XO

[dbsousa]

Re: Interesting Megastructures

 

My latest game takes place in an O'Neill Cylinder 500 Miles long, with a 50 Mile diameter. Centripedal Force replaces Gravity, and bullets fly in odd arcs that depend on your facing. To simulate this, I doubled the Range modifiers, unless characters make an AK roll to get their bearings, fire a shot to determine their bearings, or have bump of direction and the appropriate WF.

[Pfathai]

Re: Interesting Megastructures

 

Or you could build a Smoke Ring. On purpose. See the Integral Trees by Larry Niven

[Nyrath]

Re: Interesting Megastructures

 

In Edgar Rice Burrough's BEYOND THE FARTHEST STAR, he has a sort of Kemper Rosette inside a Smoke Ring. That is, a series of ten planets sharing the same orbit, joined by lanes of air. This means that intrepid adventurers can travel from planet to planet with an airplane.