Cities in space - Singles or clusters?

From: spacesettlers@yahoogroups.com [mailto:spacesettlers@yahoogroups.com] On Behalf Of Darren

> I dont know but I have huge reservations about a frame filled
> with habitats so large that in encircles the Earth. Im unsure
> of the stability of the ring, I seem to remember there being
> some problem with the stability of the ring in the ring-world
> book,

That's right. One could build an arc, and stop just short of joining the ends, and there would be no stability problem. The stability problem of Ringworld was a consequence of the fact that the ring was a continuous, joined structure; one side of the ring could pull over the other. But every part of an arc should orbit just as would a single object at that point on the orbit, and there should be no stability problems.

But it does occur to me that circular orbits must be assumed. An arc in an even slightly elliptical orbit would have a problem with stretching at perigee, and compression at apogee. So one would need to stabilize against any force tending to shift the orbit away from zero eccentricity.

Regards,

Mike Combs