Re: Article from space.com -- "Deadly Radiation Spurs Life"

[Jim Muckerheide <jmuckerheide@delphi.com>]

Rick, group,

Actually I don't see a conflict. It seems the "deadly" or "lethal" radiation
refers to the source levels at/near the planet, but the bacteria that could be
living on this energy are in a deep-below-the-surface lake, at much lower
radiation levels (and bacteria could find thousands of Gy "livable", as they
do here), although I haven't been able to get a copy of the Nature paper by
Chyba (technically a "Brief Communication") I've yet to see the calculated
estimates of these levels, or the biological basis for anticipating 

This is still consistent with radiation being essential to biological
functions. We also have deep-earth bacteria that likely depend on radiation
for life-cycle energy. And the fact that the deep-ocean hydrothermal vent
communities of much higher-order animals likely depend on the energy from the
massive radioactivity discharges from the vents (that stay locally). 

A year or so ago the biologists were so desperate to find the life-cycle
energy needed, that one paper was reported (on NPR) as trying to quantify the
energy from "the faint luminescence on _some_ of the animals" as a source
(presumably the "sulfate chemistry life-cycle energy" thesis had failed, as
would be expected). 

Note that even the geochemistry people know not to be explicit about these
massive deep-sea sources because it might upset the issue of the disposal of
nuclear waste in the ocean as being unacceptable!?  Since then there was a
report that there were greater sources from the "cold seeps" that exhaust
through the areas surrounding the vents themselves. (This seems a little like
the fact that massively more radium is being discharged to the ocean from
continental groundwater through a "pumping" action by tidal forces directly
through the continental shelf areas than is discharged through the major
rivers.)

Regards, Jim
Radiation, Science, and Health
muckerheide@mediaone.net
==============================

Rick_Strickert@radian.com wrote:
> 
> Jim Hardeman wrote:
> 
> *       I would think that we in the profession would
> *       understand what was being said, but what
> *       is John Q. Public going to think about that story?
> 
> I wrote to Robert Britt about the use of "lethal" and "deadly" in describing
> radiation that may (according to some) sustain life (if it exists) on
> Europa.  He replied that his purpose in using the terms was to present "an
> interesting twist of fate", showing a paradoxical aspect of radiation.  In
> that sense he defended the terms as acceptable using a writer's 'literary
> license.'  And Britt also claimed "our intelligent readers" would not
> associate the use of these terms with any negative connotations toward the
> nuclear industry.
> 
> Does someone want to ask John Q. Public if he is an intelligent reader?
> 
> Rick Strickert, Ph.D.
> Radian International
> Austin, TX
> 
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