Effective use of natural sunlight in a habitat.

On 7/25/07, ANTIcarrot wrote:
(...)
> Which is more common, copper or silicon/oxygen? If you're building one
> habitat it doesn't matter, but if you're building tens of thousands you want
> common elements for the millions of miles of wiring inside.
(...)

The rule-of-thumb is that the lighter the element, the more abundant
it is throughout the Universe. (Though local conditions may create
drastic exceptions for that rule of thumb.) So, as a general rule
silicon/oxygen would be more common than copper.