On Thu, 18 Sep 2003 23:53:38 +0100, Jonathan Silverlight
wrote:

In message , Steve Willner
writes
The nitrogen-15 carriers in IDPs have not been securely identified but are
possibly organic macromolecules or polycyclic aromatic hydrocarbons (PAHs).
It is thus possible that the additional parent(s) of cometary CN may belong
to this ensemble of organic substances.

In article ,
Jonathan Silverlight writes:
I can't help feeling that Chandra Wickramasinghe is going to like that
observation.

I don't see why. PAH's are widely accepted as dust constituents
these days, and there is no indication they are biological. Quite
the contrary, I should think. Their structure is multiple "benzene
rings." (Visualize those small hexagonal bathroom tiles.) Are such
structures known in biology?

That was my point! Hoyle and Wickramasinghe claimed that the spectra
they recorded were biogenic, rather than just organic, for instance. And
the nitrogen-containing macromolecules _are_ suggestive of "interesting"
molecules.

well, they're interesting to the organic chemist, if nothing else from
the perspective of how they formed. since organic chemists are known
as pot boilers, how you can get complex organic compounds in a vacuum
under all kinds of radiation is even more interesting...

But thinking about hexagonal tiles reminds me of something scary.
Remember the structure of the Andromeda Strain? ;-)

hehe. it sure made for a good story. i saw it as a kid and was
pretty creeped out. i look at it now and just chuckle....

i forget the ep, but McCoy says to Kirk: dammit, i'm a surgeon, not a
bricklayer!