Effective use of natural sunlight in a habitat.

Oxygen and Silicon are both luckily quite relatively abundant. The universe is almost entirely Hydrogen and Helium with just a dash of everything else. However , like fresh water here on Earth, its not evenly distributed. If we build colonies in the asteroid belt just past Mars, carbon, iron, silicon, oxides, and nickel will be quite abundant. Copper is not generally very common. I'm quite certain that flexibility will be needed, and settlements will be built using whatever materials are most readily available and affordable. Iron is common both in the asteroid belt and in the comet belt and cloud. Water is also common in the Kuiper belt and Oort cloud.

Interestingly, Iron is fairly common even though it is quite heavy. It is especially common in rocky bodies (planets and asteroids). I dont know this, but I suspect the reason it's so common is that iron is the first element too large for nuclear fusion, and too small for nuclear fission. It's a sort of natural stopping point for naturally occurring nuclear processes. Its also very handy that its so useful to us.

Douglas May
CWA Local 6215 - Steward

From: Lucio de Souza Coelho
To: spacesettlers@yahoogroups.com
Sent: Wednesday, July 25, 2007 12:49:36 PM
Subject: Re: [spacesettlers] Re: 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.