[extropy-chat] Suicide the Green way

[Eugen Leitl]

On Mon, Nov 20, 2006 at 09:17:42PM -0800, spike wrote:

> No, but for a light sail boron would have no advantage over lithium, which
> does reflect well in the lower frequencies.

Actually, boron has the vast advantage of forming temperature-resistant
fibres (you have certainly heard of boron-reinforced aluminum composite).

Whereas, lithium, why don't you try making a mirror from mercury with
an operating temperature >>300 K?
 
> We couldn't keep them cold enough to stay solid.  Even in deep space the
> atoms would pick up enough energy from stray photons to sublime.  I think
> that stuff is gone as soon as it hits about 14 kelvin.

Why not making a mirror from clear silica? It is certainly a much
better mirror than solid hydrogen.

Btw, since you mentioned DNA in space, of course you know that UV
would fragment it to bits, right? And that human ash doesn't contain
at all much carbon, being calcinated minerals?
 
> We can make the mirrors on the deck if we use aluminum.  If we take a large
> inflatable surface, we could probably vapor deposit pure lithium onto it in
> space, but I am not sure there is much weight advantage once one takes into
> account the structural strength of aluminum.  Let me look this up tomorrow
> Robert.  My reference material is at the office.  My intuition is that for
> reflectivity and strength, aluminum packs a lotta bang for the buck in solar
> sails.

I'm rooting for rime-coated spider silk. Makes at least as much sense.

-- 
Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org
______________________________________________________________
ICBM: 48.07100, 11.36820            http://www.ativel.com
8B29F6BE: 099D 78BA 2FD3 B014 B08A  7779 75B0 2443 8B29 F6BE
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 191 bytes
Desc: Digital signature
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20061121/89e19b8c/attachment.bin>