>Well, I was perhaps overstating it when I said "any" Dyson sphere. If
>you define a Dyson sphere as simply "enclose the star, by hook or by
>crook" than sure, you could do it with maybe a solar systems worth of
>mass, less even, if you only have a few very solid areas and much of
>the sphere is only a few inches thick and not that dense.
Most of the serious speculative pieces I've seen on whether it's really possible seem to lean toward a kind of mesh, in some cases with gaps big enough to drive a gas giant through, rather than a literal sphere.
The Zeta Cygni sphere, though... well, the thickness varies somewhat and it's not solid clear through everywhere, but it averages around a quarter-mile and it's definitely not made of low-density materials. The outer shell is tritanium (the same material most starship hulls are made of) with a surface coating of carbon neutronium (and no, I don't care to have the "neutronium" argument again) about the thickness of the gold plating on a cheap trophy.
Interestingly, the damage the sphere sustained during the Second Battle of Zeta Cygni (despite having been hilariously exaggerated in the best-known motion picture depicting those events—an explosion capable of propelling an Alaska-class battleship half an astronomical unit in a few seconds, forsooth) provided one of the earliest and best opportunities to examine its internal structure in a relatively anonymous zone, far from any of the gates or other obvious access points. From examination of the AT&T breach and subsequent expeditions to other points within, we know that the sphere's internal structures are made of a wide range of metallic and semi-metallic materials, some of which have not yet been classified by 2410 science, but while some of them are fairly lightweight (carbon-carbon lattice structures, etc.), none is what you would call insubstantial.
Even taking into account the negative mass of the charged obscurium-290 components in the stellar energy collection zones, a core sample of an "average" square meter would be very, very heavy. As Don Griffin put it once, near the end of an IPO office New Year's party that involved a substantial quantity of apple cider, "There is a fuckload of atoms flying in formation here."
(In the course of that same semi-shithammered discussion with the Chief, Don opined that the sphere must be some kind of engineering demonstration, because, he argued, any civilization technically advanced enough to construct one would long since have progressed past the point of having any practical use for it, to wit: the Time Lords don't even have one, and the Time Lords have one of feckin' everything.)
Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
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