Jonathan Silverlight wrote in message ...
In message , Ron Baalke
writes

http://www.eso.org/outreach/press-re.../pr-25-03.html

ESO Press Release 25/03
12 September 2003
For immediate release

Optical Detection of Anomalous Nitrogen in Comets

VLT Opens New Window towards Our Origins


Huge snip


Macromolecules in space

The astronomers think that the new results indicate that the HCN-molecule
cannot be the only "parent" of the CN-molecule; the latter must also be
produced by some as yet unknown parent(s) in which the nitrogen-15 isotope
is even more abundant.

In this connection, it is very interesting that an "excess" of nitrogen-15
is also known to exist in interplanetary dust particles (IDPs), captured by
high-flying aircraft in the Earth's atmosphere. They represent the oldest
material in the solar system that can be subjected to detailed laboratory
analysis. Many of these particles are thought to originate from passing
comets - this possibility is obviously supported by the new measurements.

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.

I can't help feeling that Chandra Wickramasinghe is going to like that
observation.


Good point. Also, life is known to be a primary cause of highly
variable isotope fractionation.


Bob Clark