"Real" ringworlds

narf poit chez BOOM · #1 May 13th, 2003, 05:31 AM

niven did a nice listing of various big stuff in one of his books, including how to get a ringworld to move, magnetic, spinning, sun for fuel. am i to brief sometimes?

[ May 13, 2003, 04:31: Message edited by: narf poit chez BOOM ]

Aloofi · #2 May 13th, 2003, 11:19 PM

Maybe an sphere world should be as big as a Red Giant, but then of course it would overlap the other planets.....
One question, when an sphere world is build, isn't it suppose to block the sunlight completely, thus making all the other planets in the solar system too cold to be habitable without domes?

Primogenitor · #3 May 14th, 2003, 12:10 AM

A bit of background on ringworlds etc.

Niven did write 3 very good books based on a ringworld, including all the physics required etc. Also spawned an RPG and several other books.

It basicly works out that the RW needs to be made of a material as strong as an atomic nucleus (imposisble). To generate gravity its spun at 770 million miles per second around the sun. To do this requires as much energy as our sun produces in several billion years and is therefore impossible. Day/night is generated by panels (Shadow squares) on an inner orbit. Both these panels and the ringworld are not in stable orbits; i.e. if an asteroid hits either panels or RW they would eventually drift and crash into the sun, or each other. This also happens if there is a gravity disturbance, by another planet for example. Corrected by giant thrusters of some sort. Atmosphere is held in by walls 1600 km high at the endge, however if anything punctures the bottom, all the air is forced out and the resuting thrust crashes it into the star. Again.
It has a mass that is only about 350 times that of earth, it is about a million miles wide and about 600 mllion miles long, all habitable. Thats about 3 million earths! Big, very big.

Desdinova · #4 May 14th, 2003, 12:13 AM

if you can put one more impossible in there we can all go have breakfast at Milliways.

narf poit chez BOOM · #5 May 14th, 2003, 12:13 AM

we couldn't do it, but someone with 90 million years of research probably could. if you could find some way of lowering inertia....

Primogenitor · #6 May 14th, 2003, 12:58 AM

The problem is, if you can build one of these, why do you need it? You would probably have mastered mass-energy convserion, intergalactic travel, and many other things. So why go through all the effort? Yes one of these has the area of 3 million planets, but thats only a fraction of all the planets in the galaxy.

Primogenitor · #7 May 14th, 2003, 01:04 AM

sphereworlds: a how-to guide

A typical sphereworld is a solid shell, however without anti-grav everything falls into the sun. If you spin it then all the atmosphere moves to the equator and it bulges. You could cover the inside with solar cells and inhabit the outside.

Another aproach is to use a large network of orbiting platforms, like satalites. They dont have gravity and you would need a lot to completly block the sun complelely however. Also if one crashed then you would get a chain reaction.

My personal favourite would be to build a set of ringworlds, all at diffferent angles within each other.